Add returns and charts slice (3d-9b)

9 files changed, 981 insertions, 7 deletions

diff --git a/qa/driver/browser-test.js b/qa/driver/browser-test.js
index 4a4b799..6403dc5 100644
--- a/qa/driver/browser-test.js
+++ b/qa/driver/browser-test.js
@@ -25,6 +25,7 @@ let createdFundResponse = null;
 let lastOrdersResponse = null;
 let lastConfirmResponse = null;
 let lastRedemptionConfirmResponse = null;
+let lastReturnsResponse = null;
 
 function check(name, ok, detail) {
   results.push({ name, ok, detail: detail || "" });
@@ -103,7 +104,7 @@ async function summaryLabelExists(page, label, name) {
         if (!createdFundResponse) createdFundResponse = await r.json();
       } catch {}
     }
-    if (r.url().includes("/api/funds/") && !r.url().includes("/orders") && r.request().method() === "GET" && r.status() < 400) fundGets++;
+    if (/\/api\/funds\/[0-9a-f-]{36}$/i.test(new URL(r.url()).pathname) && r.request().method() === "GET" && r.status() < 400) fundGets++;
     if (r.url().includes("/api/funds/") && r.url().includes("/orders") && r.request().method() === "GET" && r.status() < 400) {
       orderGets++;
       try {
@@ -129,6 +130,11 @@ async function summaryLabelExists(page, label, name) {
         lastPositionsResponse = await r.json();
       } catch {}
     }
+    if (r.url().includes("/returns") && r.request().method() === "GET" && r.status() < 400) {
+      try {
+        lastReturnsResponse = await r.json();
+      } catch {}
+    }
     if (r.status() >= 400 && !/\/api\/instruments\//.test(r.url()) && !/\/orders/.test(r.url()) && !/\/redemptions/.test(r.url()) && !/\/capital/.test(r.url())) {
       consoleErrors.push("resource " + r.status() + ": " + r.url());
     }
@@ -175,6 +181,7 @@ async function summaryLabelExists(page, label, name) {
     await redeemScenario(page);
     await capitalScenario(page);
     await dividendScenario(page);
+    await returnsScenario(page);
   } finally {
     check("G1 无浏览器控制台/页面错误", consoleErrors.length === 0, consoleErrors.slice(0, 3).join(" | "));
     await browser.close();
@@ -411,6 +418,51 @@ async function dividendScenario(page) {
   await page.screenshot({ path: SHOTS + "/15-dividend-history.png" });
 }
 
+async function returnsScenario(page) {
+  // R 系列: 收益与资产曲线（接 L 场景：现金 5442.99，持仓 50.00000000 @1.1902 = 59.51）
+  await page.waitForSelector(".returns-panel", { timeout: 10000 });
+  const eyebrow = ((await page.textContent(".returns-panel .eyebrow")) || "").trim();
+  check("R1 收益面板 eyebrow 为 10 / RETURNS", eyebrow === "10 / RETURNS", eyebrow);
+
+  lastReturnsResponse = null;
+  await page.click(".returns-refresh-action");
+  for (let i = 0; i < 200 && lastReturnsResponse === null; i++) {
+    await page.waitForTimeout(100);
+  }
+  const returns = lastReturnsResponse || {};
+  const points = Array.isArray(returns.points) ? returns.points : [];
+  const last = points.length > 0 ? points[points.length - 1] : {};
+  check(
+    "R2 收益接口返回现金流调整后的总资产与累计收益",
+    returns.pending === false &&
+      last.date === "2026-09-21" &&
+      last.totalAssets === "5502.50" &&
+      last.cumulativeReturn === "2.50" &&
+      last.cash === "5442.99" &&
+      last.holdingsValue === "59.51" &&
+      typeof last.unitNav === "string" &&
+      last.unitNav.length > 0,
+    JSON.stringify(returns).slice(0, 280)
+  );
+
+  await page.waitForSelector(".returns-panel .metric-strip", { timeout: 15000 });
+  const metricText = ((await page.textContent(".returns-panel .metric-strip")) || "");
+  const noteText = ((await page.textContent(".returns-panel .returns-note")) || "");
+  const markers = await page.locator(".returns-chart circle").count();
+  check(
+    "R3 收益卡片与 API 一致、图表有点且不补零",
+    metricText.includes("总资产") &&
+      metricText.includes("5502.50") &&
+      metricText.includes("累计收益") &&
+      metricText.includes("2.50") &&
+      metricText.includes("数据更新时间") &&
+      markers >= 1 &&
+      noteText.includes("不补零"),
+    `metrics=${metricText.slice(0, 160)} markers=${markers}`
+  );
+  await page.screenshot({ path: SHOTS + "/16-returns-curve.png" });
+}
+
   const failed = results.filter((r) => !r.ok);
   console.log(`\n==== ${results.length - failed.length}/${results.length} passed ====`);
   process.exit(failed.length > 0 ? 1 : 0);
diff --git a/src/FundLab.Api/App.fs b/src/FundLab.Api/App.fs
index 38debc3..fc174e5 100644
--- a/src/FundLab.Api/App.fs
+++ b/src/FundLab.Api/App.fs
@@ -193,6 +193,27 @@ type CapitalDepositResponse =
         createdAt: string
     }
 
+type FundReturnsPointResponse =
+    {
+        date: string
+        pending: bool
+        totalAssets: string option
+        unitNav: string option
+        cash: string
+        reservedCash: string
+        holdingsValue: string option
+        cumulativeReturn: string option
+        netExternalFlow: string
+    }
+
+type FundReturnsResponse =
+    {
+        fundId: Guid
+        pending: bool
+        dataUpdatedAt: string option
+        points: FundReturnsPointResponse list
+    }
+
 type ApiErrorResponse =
     {
         error: string
@@ -677,6 +698,40 @@ module App =
                 with _ ->
                     errorResponse 500 "PERSISTENCE_ERROR" "dividend persistence failed" next ctx
 
+    let private returnsPointResponse (point: FundReturnsPoint) : FundReturnsPointResponse =
+        {
+            date = dateText point.Date
+            pending = point.Pending
+            totalAssets = point.TotalAssets |> Option.map cashText
+            unitNav = point.UnitNav |> Option.map unitNavText
+            cash = cashText point.Cash
+            reservedCash = cashText point.ReservedCash
+            holdingsValue = point.HoldingsValue |> Option.map cashText
+            cumulativeReturn = point.CumulativeReturn |> Option.map cashText
+            netExternalFlow = cashText point.NetExternalFlow
+        }
+
+    let private getFundReturns (repository: FundRepository) (fundIdText: string) : HttpHandler =
+        fun next ctx ->
+            match Guid.TryParse fundIdText with
+            | false, _ -> errorResponse 400 "INVALID_FUND_ID" "fund id must be a UUID" next ctx
+            | true, fundId ->
+                try
+                    match repository.GetFundReturns fundId with
+                    | None -> errorResponse 404 "FUND_NOT_FOUND" "fund was not found" next ctx
+                    | Some returns ->
+                        json
+                            ({
+                                fundId = returns.FundId
+                                pending = returns.Pending
+                                dataUpdatedAt = returns.DataUpdatedAt |> Option.map timestampText
+                                points = returns.Points |> List.map returnsPointResponse
+                            } : FundReturnsResponse)
+                            next
+                            ctx
+                with _ ->
+                    errorResponse 500 "PERSISTENCE_ERROR" "returns persistence failed" next ctx
+
 
 
 
@@ -1291,6 +1346,7 @@ module App =
                 POST >=> routef "/funds/%s/rebalance/plans/%s/execute" (fun (fundId, planId) -> executeRebalancePlan repository fundId planId)
                 POST >=> routef "/funds/%s/dividends" (createDividend repository)
                 GET >=> routef "/funds/%s/dividends" (getDividends repository)
+                GET >=> routef "/funds/%s/returns" (getFundReturns repository)
                 GET >=> routef "/funds/%s" (getFund repository)
             ]
             @ (marketData |> Option.map marketDataRoutes |> Option.defaultValue [])
diff --git a/src/FundLab.Api/Persistence.fs b/src/FundLab.Api/Persistence.fs
index 973544f..a8abd94 100644
--- a/src/FundLab.Api/Persistence.fs
+++ b/src/FundLab.Api/Persistence.fs
@@ -142,6 +142,7 @@ type FundRecord =
         AvailableCash: decimal
         ReservedCash: decimal
         Status: string
+        CreatedAt: DateTimeOffset
     }
 
 type FundWriteResult =
@@ -433,6 +434,30 @@ type CapitalDepositWriteResult =
     | CapitalDepositInvalid of string
     | CapitalDepositFundNotFound
 
+/// One reconstructed end-of-day fund valuation. `TotalAssets`/`UnitNav`/
+/// `HoldingsValue`/`CumulativeReturn` are `None` when a held instrument has no
+/// NAV observation dated on or before `Date`: the value is unknown, never zero.
+type FundReturnsPoint =
+    {
+        Date: DateOnly
+        Pending: bool
+        TotalAssets: decimal option
+        UnitNav: decimal option
+        Cash: decimal
+        ReservedCash: decimal
+        HoldingsValue: decimal option
+        CumulativeReturn: decimal option
+        NetExternalFlow: decimal
+    }
+
+type FundReturns =
+    {
+        FundId: Guid
+        Pending: bool
+        DataUpdatedAt: DateTimeOffset option
+        Points: FundReturnsPoint list
+    }
+
 type FundRepository(connectionString: string) =
     let cashMaximum = 999999999999999999.99m
     let unitNavMaximum = 99999999999999999999.99999999m
@@ -731,6 +756,7 @@ type FundRepository(connectionString: string) =
             AvailableCash = fund.AvailableCash
             ReservedCash = fund.FrozenCash
             Status = statusText fund.Status
+            CreatedAt = DateTimeOffset.UtcNow
         }
 
     let recordFromReader (reader: DbDataReader) =
@@ -744,6 +770,7 @@ type FundRepository(connectionString: string) =
             AvailableCash = reader.GetDecimal(6)
             ReservedCash = reader.GetDecimal(7)
             Status = reader.GetString(8)
+            CreatedAt = reader.GetFieldValue<DateTimeOffset>(9)
         }
 
     let dateTimeOffsetFromReader (reader: DbDataReader) index =
@@ -811,7 +838,7 @@ type FundRepository(connectionString: string) =
                 transaction
                 """
                 SELECT id, name, currency, initial_cash, initial_unit_nav,
-                       is_synthetic, available_cash, reserved_cash, status
+                       is_synthetic, available_cash, reserved_cash, status, created_at
                 FROM funds
                 WHERE id = @fund_id
                 """
@@ -4043,3 +4070,203 @@ type FundRepository(connectionString: string) =
             )
 
         records |> Seq.toList
+
+    /// Reconstructs the fund's asset and unit-NAV history from confirmed ledger
+    /// events plus persisted NAV observations. Unit NAV is rebuilt by issuing fund
+    /// units for external capital deposits at the previously known unit NAV, so a
+    /// deposit never moves the unit NAV. Values that cannot be known at a date stay
+    /// `None`; nothing is filled with zero.
+    member this.GetFundReturns(fundId: Guid) : FundReturns option =
+        match this.GetFund fundId with
+        | None -> None
+        | Some fund ->
+            let today = ConfirmationPolicy.shanghaiDate DateTimeOffset.UtcNow
+            let deposits = this.GetCapitalDeposits fundId
+            let orders = this.GetSubscriptionOrders fundId
+            let redemptions = this.GetRedemptionOrders fundId
+            let dividends = this.GetDividendRecords fundId
+
+            let heldCodes =
+                [ yield! orders |> List.map (fun order -> order.FundCode)
+                  yield! redemptions |> List.map (fun order -> order.InstrumentCode) ]
+                |> List.distinct
+
+            let navByCode =
+                heldCodes
+                |> List.map (fun code -> code, this.GetNav(code, None, Some today))
+                |> Map.ofList
+
+            let firstHoldingDate (code: string) =
+                orders
+                |> List.filter (fun order -> order.FundCode = code && order.Status = "confirmed")
+                |> List.map (fun order -> order.TradeDate)
+                |> List.sort
+                |> List.tryHead
+
+            let navDates =
+                heldCodes
+                |> List.collect (fun code ->
+                    match firstHoldingDate code with
+                    | None -> []
+                    | Some startDate ->
+                        navByCode.[code]
+                        |> List.filter (fun observation ->
+                            observation.NavDate >= startDate && observation.NavDate <= today)
+                        |> List.map (fun observation -> observation.NavDate))
+                |> Set.ofList
+
+            let creationDate = ConfirmationPolicy.shanghaiDate fund.CreatedAt
+
+            let dividendCredited =
+                dividends
+                |> List.filter (fun record -> record.Status = "cash_credited" || record.Status = "succeeded")
+
+            let hasActivity =
+                not (List.isEmpty deposits)
+                || not (List.isEmpty orders)
+                || not (List.isEmpty redemptions)
+                || not (List.isEmpty dividendCredited)
+                || not (Set.isEmpty navDates)
+
+            if not hasActivity then
+                Some
+                    {
+                        FundId = fundId
+                        Pending = false
+                        DataUpdatedAt = None
+                        Points = []
+                    }
+            else
+                let eventDates =
+                    [ yield creationDate
+                      yield! deposits |> List.map (fun deposit -> ConfirmationPolicy.shanghaiDate deposit.CreatedAt)
+                      yield! orders |> List.map (fun order -> order.TradeDate)
+                      yield! redemptions |> List.map (fun order -> order.TradeDate)
+                      yield! dividendCredited |> List.map (fun record -> record.NavDate) ]
+                    |> Set.ofList
+
+                let dates =
+                    Set.union eventDates navDates
+                    |> Set.toList
+                    |> List.sort
+
+                let dataUpdatedAt =
+                    navByCode
+                    |> Map.toList
+                    |> List.collect snd
+                    |> List.map (fun observation -> observation.LastSeenAt)
+                    |> List.sortDescending
+                    |> List.tryHead
+
+                let latestNavOnOrBefore (code: string) (date: DateOnly) =
+                    match Map.tryFind code navByCode with
+                    | None -> None
+                    | Some observations ->
+                        observations
+                        |> List.filter (fun observation -> observation.NavDate <= date && observation.Nav > 0m)
+                        |> List.sortByDescending (fun observation -> observation.NavDate, observation.SourceCollectedAt)
+                        |> List.tryHead
+
+                let mutable availableCash = fund.InitialCash
+                let mutable reservedCash = 0m
+                let mutable fundUnits = if fund.InitialUnitNav > 0m then fund.InitialCash / fund.InitialUnitNav else 0m
+                let mutable lastKnownNav = if fund.InitialUnitNav > 0m then Some fund.InitialUnitNav else None
+                let positions = System.Collections.Generic.Dictionary<string, decimal>()
+                let mutable cumulativeDeposits = 0m
+                let points = ResizeArray<FundReturnsPoint>()
+
+                for date in dates do
+                    for deposit in deposits do
+                        if ConfirmationPolicy.shanghaiDate deposit.CreatedAt = date then
+                            availableCash <- availableCash + deposit.Amount
+                            cumulativeDeposits <- cumulativeDeposits + deposit.Amount
+
+                            match lastKnownNav with
+                            | Some nav when nav > 0m -> fundUnits <- fundUnits + deposit.Amount / nav
+                            | _ -> ()
+
+                    for order in orders do
+                        if order.TradeDate = date then
+                            if order.Status = "confirmed" then
+                                let residual = order.ConfirmedResidualCash |> Option.defaultValue 0m
+                                availableCash <- availableCash + residual - order.ReservedTotal
+
+                                let units = order.ConfirmedUnits |> Option.defaultValue 0m
+                                let current =
+                                    match positions.TryGetValue order.FundCode with
+                                    | true, value -> value
+                                    | _ -> 0m
+
+                                positions.[order.FundCode] <- current + units
+                            else
+                                availableCash <- availableCash - order.ReservedTotal
+                                reservedCash <- reservedCash + order.ReservedTotal
+
+                    for order in redemptions do
+                        if order.TradeDate = date && order.Status = "confirmed" then
+                            let current =
+                                match positions.TryGetValue order.InstrumentCode with
+                                | true, value -> value
+                                | _ -> 0m
+
+                            positions.[order.InstrumentCode] <- current - order.Units
+                            availableCash <- availableCash + (order.ConfirmedProceeds |> Option.defaultValue 0m)
+
+                    for record in dividendCredited do
+                        if record.NavDate = date then
+                            availableCash <- availableCash + (record.GrossCash |> Option.defaultValue 0m)
+
+                    let mutable pending = false
+                    let mutable holdingsValue = 0m
+
+                    for KeyValue(code, units) in positions do
+                        if units > 0m then
+                            match latestNavOnOrBefore code date with
+                            | Some observation -> holdingsValue <- holdingsValue + units * observation.Nav
+                            | None -> pending <- true
+
+                    let netExternalFlow = fund.InitialCash + cumulativeDeposits
+
+                    if pending then
+                        points.Add(
+                            {
+                                Date = date
+                                Pending = true
+                                TotalAssets = None
+                                UnitNav = None
+                                Cash = availableCash
+                                ReservedCash = reservedCash
+                                HoldingsValue = None
+                                CumulativeReturn = None
+                                NetExternalFlow = netExternalFlow
+                            }
+                        )
+                    else
+                        let totalAssets = availableCash + reservedCash + holdingsValue
+                        let unitNav = if fundUnits > 0m then Some(totalAssets / fundUnits) else None
+
+                        match unitNav with
+                        | Some nav -> lastKnownNav <- Some nav
+                        | None -> ()
+
+                        points.Add(
+                            {
+                                Date = date
+                                Pending = false
+                                TotalAssets = Some totalAssets
+                                UnitNav = unitNav
+                                Cash = availableCash
+                                ReservedCash = reservedCash
+                                HoldingsValue = Some holdingsValue
+                                CumulativeReturn = Some(totalAssets - netExternalFlow)
+                                NetExternalFlow = netExternalFlow
+                            }
+                        )
+
+                Some
+                    {
+                        FundId = fundId
+                        Pending = points |> Seq.exists (fun point -> point.Pending)
+                        DataUpdatedAt = dataUpdatedAt
+                        Points = points |> Seq.toList
+                    }
diff --git a/src/FundLab.Web/App.fs b/src/FundLab.Web/App.fs
index 6ce48f0..f1e6df6 100644
--- a/src/FundLab.Web/App.fs
+++ b/src/FundLab.Web/App.fs
@@ -29,6 +29,14 @@ type ChartPoint =
         nav: string
     }
 
+type SeriesPoint =
+    {
+        x: float
+        y: float
+        label: string
+        value: string
+    }
+
 module Chart =
     let private invariant = CultureInfo.InvariantCulture
 
@@ -69,6 +77,37 @@ module Chart =
                     nav = observation.nav
                 })
 
+    /// Normalizes one named series over a shared, already ordered date axis. Dates
+    /// without a value are omitted (a gap, never a zero). `x` is the position on the
+    /// full axis so two series stay aligned; `y` is normalized within the series.
+    let seriesPoints (dates: string list) (values: (string * string) list) : SeriesPoint list =
+        let parsed =
+            values
+            |> List.choose (fun (date, text) ->
+                match Decimal.TryParse(text, NumberStyles.Float, invariant) with
+                | true, value -> Some(date, value, text)
+                | false, _ -> None)
+
+        match parsed with
+        | [] -> []
+        | _ ->
+            let numbers = parsed |> List.map (fun (_, value, _) -> value)
+            let minimum = List.min numbers
+            let maximum = List.max numbers
+            let range = maximum - minimum
+            let count = List.length dates
+            let lookup = parsed |> List.map (fun (date, value, text) -> date, (value, text)) |> Map.ofList
+
+            dates
+            |> List.mapi (fun index date ->
+                match Map.tryFind date lookup with
+                | None -> None
+                | Some(value, text) ->
+                    let x = if count <= 1 then 0.5 else float index / float (count - 1)
+                    let y = if range = 0M then 0.5 else float ((value - minimum) / range)
+                    Some { x = x; y = y; label = date; value = text })
+            |> List.choose id
+
 type RawOptionalText =
     {
         case: string
@@ -239,6 +278,27 @@ type RawPositions =
         positions: RawPosition array
     }
 
+type RawReturnsPoint =
+    {
+        date: string
+        pending: bool
+        totalAssets: obj
+        unitNav: obj
+        cash: string
+        reservedCash: string
+        holdingsValue: obj
+        cumulativeReturn: obj
+        netExternalFlow: string
+    }
+
+type RawReturns =
+    {
+        fundId: string
+        pending: bool
+        dataUpdatedAt: obj
+        points: RawReturnsPoint array
+    }
+
 type CreateAttempt =
     {
         idempotencyKey: string
@@ -435,6 +495,26 @@ type Positions =
         positions: Position list
     }
 
+type ReturnsPoint =
+    {
+        date: string
+        pending: bool
+        totalAssets: string option
+        unitNav: string option
+        cash: string
+        reservedCash: string
+        holdingsValue: string option
+        cumulativeReturn: string option
+        netExternalFlow: string
+    }
+
+type FundReturns =
+    {
+        pending: bool
+        dataUpdatedAt: string option
+        points: ReturnsPoint list
+    }
+
 module Api =
     [<Import("searchInstruments", "./src/api.js")>]
     let searchInstruments (token: string) (query: string) : JS.Promise<RawSearchResponse> = jsNative
@@ -475,6 +555,9 @@ module Api =
     [<Import("getDividends", "./src/api.js")>]
     let getDividends (token: string) (fundId: string) : JS.Promise<RawDividend array> = jsNative
 
+    [<Import("getReturns", "./src/api.js")>]
+    let getReturns (token: string) (fundId: string) : JS.Promise<RawReturns> = jsNative
+
     [<Import("createCapitalDeposit", "./src/api.js")>]
     let createCapitalDeposit (token: string) (fundId: string) (payload: CreateCapitalPayload) : JS.Promise<obj> = jsNative
 
@@ -637,6 +720,26 @@ module Api =
             createdAt = raw.createdAt
         }
 
+    let decodeReturnsPoint (raw: RawReturnsPoint) : ReturnsPoint =
+        {
+            date = raw.date
+            pending = raw.pending
+            totalAssets = decodeOptionalText raw.totalAssets
+            unitNav = decodeOptionalText raw.unitNav
+            cash = raw.cash
+            reservedCash = raw.reservedCash
+            holdingsValue = decodeOptionalText raw.holdingsValue
+            cumulativeReturn = decodeOptionalText raw.cumulativeReturn
+            netExternalFlow = raw.netExternalFlow
+        }
+
+    let decodeReturns (raw: RawReturns) : FundReturns =
+        {
+            pending = raw.pending
+            dataUpdatedAt = decodeOptionalText raw.dataUpdatedAt
+            points = raw.points |> Array.map decodeReturnsPoint |> Array.toList
+        }
+
 type Model =
     {
         token: string
@@ -706,6 +809,9 @@ type Model =
         dividendReadSeq: int
         dividendInFlight: bool
         dividends: DividendRecord list
+        returnsReadSeq: int
+        returnsInFlight: bool
+        returns: FundReturns option
         error: string option
     }
 
@@ -784,6 +890,9 @@ type Msg =
     | DividendsReadRequested
     | DividendsReadCompleted of requestId: int * records: RawDividend array
     | DividendsReadFailed of requestId: int * message: string
+    | ReturnsReadRequested
+    | ReturnsReadCompleted of requestId: int * returns: RawReturns
+    | ReturnsReadFailed of requestId: int * message: string
 
 let defaultInitialUnitNav = "1.00000000"
 
@@ -882,6 +991,9 @@ let init () =
         dividendReadSeq = 0
         dividendInFlight = false
         dividends = []
+        returnsReadSeq = 0
+        returnsInFlight = false
+        returns = None
         error = None
     }
 
@@ -1024,6 +1136,13 @@ let private readDividendsCommand token fundId requestId =
         (fun records -> DividendsReadCompleted(requestId, records))
         (fun error -> DividendsReadFailed(requestId, errorText error))
 
+let private readReturnsCommand token fundId requestId =
+    Cmd.OfPromise.either
+        (fun () -> Api.getReturns token fundId)
+        ()
+        (fun returns -> ReturnsReadCompleted(requestId, returns))
+        (fun error -> ReturnsReadFailed(requestId, errorText error))
+
 let update message model =
     match message with
     | TokenChanged token ->
@@ -1095,6 +1214,9 @@ let update message model =
                 dividendReadSeq = model.dividendReadSeq + 1
                 dividendInFlight = false
                 dividends = []
+                returnsReadSeq = model.returnsReadSeq + 1
+                returnsInFlight = false
+                returns = None
                 error = None
         },
         Cmd.none
@@ -1292,9 +1414,12 @@ let update message model =
                     dividendReadSeq = model.dividendReadSeq + 1
                     dividendInFlight = false
                     dividends = []
+                    returnsReadSeq = model.returnsReadSeq + 1
+                    returnsInFlight = false
+                    returns = None
                     error = None
             },
-            Cmd.ofMsg OrdersReadRequested
+            Cmd.batch [ Cmd.ofMsg OrdersReadRequested; Cmd.ofMsg ReturnsReadRequested ]
         else
             model, Cmd.none
     | FundCreateFailed (requestId, message) ->
@@ -1389,7 +1514,7 @@ let update message model =
                     lastOrderAttempt = None
                     error = None
             },
-            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg OrdersReadRequested ]
+            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg OrdersReadRequested; Cmd.ofMsg ReturnsReadRequested ]
         else
             model, Cmd.none
     | OrderCreateFailed (requestId, fundId, message) ->
@@ -1451,7 +1576,7 @@ let update message model =
                 |> List.map (fun order -> if order.id = confirmed.id then confirmed else order)
 
             { model with confirmInFlight = false; lastConfirmAttempt = None; orders = orders; error = None },
-            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg PositionsReadRequested ]
+            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg PositionsReadRequested; Cmd.ofMsg ReturnsReadRequested ]
         else
             model, Cmd.none
     | OrderConfirmFailed (requestId, orderId, message) ->
@@ -1622,7 +1747,7 @@ let update message model =
                 |> List.map (fun order -> if order.id = confirmed.id then confirmed else order)
 
             { model with redemptionConfirmInFlight = false; lastRedemptionConfirmAttempt = None; redemptions = redemptions; error = None },
-            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg PositionsReadRequested ]
+            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg PositionsReadRequested; Cmd.ofMsg ReturnsReadRequested ]
         else
             model, Cmd.none
     | RedemptionConfirmFailed (requestId, orderId, message) ->
@@ -1678,7 +1803,7 @@ let update message model =
                     capitalNote = Some(sprintf "追加成功 + %s（现金余额已刷新）" amount)
                     error = None
             },
-            Cmd.ofMsg FundReadRequested
+            Cmd.batch [ Cmd.ofMsg FundReadRequested; Cmd.ofMsg ReturnsReadRequested ]
         else
             model, Cmd.none
     | CapitalDepositFailed (requestId, message) ->
@@ -1965,6 +2090,36 @@ let update message model =
             { model with dividendInFlight = false; error = Some message }, Cmd.none
         else
             model, Cmd.none
+    | ReturnsReadRequested ->
+        match model.createdFund with
+        | Some fund when not (String.IsNullOrWhiteSpace model.token) ->
+            let requestId = model.returnsReadSeq + 1
+
+            {
+                model with
+                    returnsReadSeq = requestId
+                    returnsInFlight = true
+                    error = None
+            },
+            readReturnsCommand model.token fund.id requestId
+        | Some _ -> { model with error = Some "请输入 API token" }, Cmd.none
+        | None -> model, Cmd.none
+    | ReturnsReadCompleted (requestId, returns) ->
+        if requestId = model.returnsReadSeq then
+            {
+                model with
+                    returns = Some(Api.decodeReturns returns)
+                    returnsInFlight = false
+                    error = None
+            },
+            Cmd.none
+        else
+            model, Cmd.none
+    | ReturnsReadFailed (requestId, message) ->
+        if requestId = model.returnsReadSeq then
+            { model with returnsInFlight = false; error = Some message }, Cmd.none
+        else
+            model, Cmd.none
 
 
 let private navText (text: string) =
@@ -3050,6 +3205,190 @@ let private dividendPanel model dispatch =
         ]
     ]
 
+let private moneyText (text: string) =
+    match Decimal.TryParse(text, NumberStyles.Float, CultureInfo.InvariantCulture) with
+    | true, value -> value.ToString("0.00", CultureInfo.InvariantCulture)
+    | false, _ -> text
+
+let private shortTimestamp (text: string) =
+    if String.IsNullOrWhiteSpace text then
+        "暂无"
+    else
+        let normalized = text.Replace("T", " ")
+        if normalized.Length >= 16 then normalized.Substring(0, 16) else normalized
+
+let private returnsChartView (points: ReturnsPoint list) =
+    let dates = points |> List.map (fun point -> point.date)
+
+    let totalSeries =
+        points
+        |> List.choose (fun point -> point.totalAssets |> Option.map (fun value -> point.date, value))
+
+    let navSeries =
+        points
+        |> List.choose (fun point -> point.unitNav |> Option.map (fun value -> point.date, value))
+
+    let totalPoints = Chart.seriesPoints dates totalSeries
+    let navPoints = Chart.seriesPoints dates navSeries
+
+    if List.isEmpty totalPoints && List.isEmpty navPoints then
+        Html.div [ prop.className "chart-empty"; prop.text "暂无收益数据" ]
+    else
+        let width = 960.0
+        let height = 320.0
+        let padding = 28.0
+        let chartWidth = width - padding * 2.0
+        let chartHeight = height - padding * 2.0
+
+        let coordinates (series: SeriesPoint list) =
+            series
+            |> List.map (fun point -> padding + point.x * chartWidth, padding + (1.0 - point.y) * chartHeight)
+
+        let gridLines =
+            [ 0 .. 4 ]
+            |> List.map (fun index ->
+                let y = padding + float index / 4.0 * chartHeight
+
+                Svg.line [
+                    svg.x1 padding
+                    svg.y1 y
+                    svg.x2 (width - padding)
+                    svg.y2 y
+                    svg.stroke "#e2e8f0"
+                    svg.strokeWidth 1
+                ])
+
+        let markers color (series: SeriesPoint list) =
+            coordinates series
+            |> List.map (fun (x, y) ->
+                Svg.circle [
+                    svg.cx x
+                    svg.cy y
+                    svg.r 3.5
+                    svg.fill color
+                ])
+
+        Html.div [
+            prop.className "chart-wrap returns-chart"
+            prop.children [
+                Svg.svg [
+                    svg.className "nav-chart"
+                    svg.viewBox (0, 0, 960, 320)
+                    svg.children [
+                        yield! gridLines
+                        if List.length totalPoints >= 2 then
+                            yield
+                                Svg.polyline [
+                                    svg.points (coordinates totalPoints)
+                                    svg.fill "none"
+                                    svg.stroke "#1e40af"
+                                    svg.strokeWidth 3
+                                ]
+                        if List.length navPoints >= 2 then
+                            yield
+                                Svg.polyline [
+                                    svg.points (coordinates navPoints)
+                                    svg.fill "none"
+                                    svg.stroke "#f59e0b"
+                                    svg.strokeWidth 3
+                                ]
+                        yield! markers "#1e40af" totalPoints
+                        yield! markers "#f59e0b" navPoints
+                    ]
+                ]
+                Html.div [
+                    prop.className "chart-axis"
+                    prop.children [
+                        Html.span [ prop.text (points |> List.head |> fun point -> point.date) ]
+                        Html.span [ prop.text (points |> List.last |> fun point -> point.date) ]
+                    ]
+                ]
+            ]
+        ]
+
+let private returnsPanel model dispatch =
+    let latest (selector: ReturnsPoint -> string option) =
+        model.returns
+        |> Option.bind (fun returns -> returns.points |> List.rev |> List.tryPick selector)
+
+    let totalAssets = latest (fun point -> point.totalAssets)
+    let cumulativeReturn = latest (fun point -> point.cumulativeReturn)
+    let updatedAt = model.returns |> Option.bind (fun returns -> returns.dataUpdatedAt)
+
+    Html.section [
+        prop.className "panel returns-panel"
+        prop.children [
+            Html.div [
+                prop.className "section-heading"
+                prop.children [
+                    Html.div [
+                        Html.p [ prop.className "eyebrow"; prop.text "10 / RETURNS" ]
+                        Html.h2 "收益与资产曲线"
+                    ]
+                    Html.span [ prop.className "section-note"; prop.text "Returns - cash-flow adjusted" ]
+                ]
+            ]
+            match model.returns with
+            | None ->
+                Html.p [ prop.className "hint"; prop.text "创建基金后可读取收益曲线。" ]
+            | Some returns when List.isEmpty returns.points ->
+                Html.p [ prop.className "hint"; prop.text "暂无收益数据" ]
+            | Some returns ->
+                Html.div [
+                    prop.className "nav-content"
+                    prop.children [
+                        Html.div [
+                            prop.className "metric-strip"
+                            prop.children [
+                                Html.div [
+                                    prop.className "metric"
+                                    prop.children [
+                                        Html.span "总资产"
+                                        Html.strong (totalAssets |> Option.map moneyText |> Option.defaultValue "暂无")
+                                    ]
+                                ]
+                                Html.div [
+                                    prop.className "metric"
+                                    prop.children [
+                                        Html.span "累计收益"
+                                        Html.strong (cumulativeReturn |> Option.map moneyText |> Option.defaultValue "暂无")
+                                    ]
+                                ]
+                                Html.div [
+                                    prop.className "metric"
+                                    prop.children [
+                                        Html.span "数据更新时间"
+                                        Html.strong (updatedAt |> Option.map shortTimestamp |> Option.defaultValue "暂无")
+                                    ]
+                                ]
+                            ]
+                        ]
+                        returnsChartView returns.points
+                        Html.p [
+                            prop.className "returns-note"
+                            prop.text "蓝线 总资产 / 橙线 单位净值（各自归一化）；缺少净值的数据点不连线，也不补零。"
+                        ]
+                        if returns.pending then
+                            Html.p [
+                                prop.className "returns-pending"
+                                prop.text "部分持有基金缺少估值日净值，相关日期标记为待更新。"
+                            ]
+                    ]
+                ]
+            Html.div [
+                prop.className "panel-actions"
+                prop.children [
+                    Html.button [
+                        prop.className "secondary-action returns-refresh-action"
+                        prop.disabled model.returnsInFlight
+                        prop.onClick (fun _ -> dispatch ReturnsReadRequested)
+                        prop.text ((if model.returnsInFlight then "读取中..." else "刷新收益曲线"): string)
+                    ]
+                ]
+            ]
+        ]
+    ]
+
 let view model dispatch =
     Html.main [
         prop.className "app-shell"
@@ -3111,6 +3450,7 @@ let view model dispatch =
             sipPanel model dispatch
             rebalancePanel model dispatch
             dividendPanel model dispatch
+            returnsPanel model dispatch
             Html.footer [ prop.className "footer-note"; prop.text "SOURCE · AKShare   /   STORAGE · PostgreSQL   /   LEDGER · CREATE & READ & SUBSCRIBE" ]
         ]
     ]
diff --git a/src/FundLab.Web/src/api.js b/src/FundLab.Web/src/api.js
index f3821f9..7606e02 100644
--- a/src/FundLab.Web/src/api.js
+++ b/src/FundLab.Web/src/api.js
@@ -123,6 +123,10 @@ export function getDividends(token, fundId) {
   return requestJson(`/api/funds/${encodeURIComponent(fundId)}/dividends`, token);
 }
 
+export function getReturns(token, fundId) {
+  return requestJson(`/api/funds/${encodeURIComponent(fundId)}/returns`, token);
+}
+
 export function createSipPlan(token, fundId, payload) {
   const body = `{"instrumentCode":${JSON.stringify(payload.instrumentCode)},"amount":${JSON.stringify(payload.amount)},"frequency":${JSON.stringify(payload.frequency)}}`;
   return requestJson(`/api/funds/${encodeURIComponent(fundId)}/sip/plans`, token, {
diff --git a/src/FundLab.Web/src/styles.css b/src/FundLab.Web/src/styles.css
index d3f0e33..016178d 100644
--- a/src/FundLab.Web/src/styles.css
+++ b/src/FundLab.Web/src/styles.css
@@ -540,6 +540,20 @@ h2 {
   background: #f8fafc;
 }
 
+.returns-note {
+  color: #64748b;
+  font-size: 11px;
+}
+
+.returns-pending {
+  color: #b45309;
+  font-size: 12px;
+}
+
+.returns-chart .nav-chart {
+  height: 300px;
+}
+
 .footer-note {
   padding: 16px 0 34px;
   font-family: "SFMono-Regular", Consolas, monospace;
diff --git a/tests/FundLab.Api.Tests/FundLab.Api.Tests.fsproj b/tests/FundLab.Api.Tests/FundLab.Api.Tests.fsproj
index 552a9bd..0024deb 100644
--- a/tests/FundLab.Api.Tests/FundLab.Api.Tests.fsproj
+++ b/tests/FundLab.Api.Tests/FundLab.Api.Tests.fsproj
@@ -26,6 +26,7 @@
     <Compile Include="OrderTests.fs" />
         <Compile Include="SipAdvanceTests.fs" />
         <Compile Include="DividendTests.fs" />
+        <Compile Include="ReturnsTests.fs" />
     <Compile Include="Program.fs" />
   </ItemGroup>
 </Project>
diff --git a/tests/FundLab.Api.Tests/ReturnsTests.fs b/tests/FundLab.Api.Tests/ReturnsTests.fs
new file mode 100644
index 0000000..01a5e10
--- /dev/null
+++ b/tests/FundLab.Api.Tests/ReturnsTests.fs
@@ -0,0 +1,233 @@
+namespace FundLab.Api.Tests
+
+open System
+open System.Text.Json
+open Npgsql
+open Xunit
+open FundLab.Api
+
+[<Collection("postgres")>]
+type ReturnsTests(fixture: PostgresFixture) =
+    let sharedRepository =
+        lazy
+            let value = FundRepository(fixture.ConnectionString)
+            value.EnsureSchema()
+            value
+
+    let repository () = sharedRepository.Value
+
+    let seedInstrument () =
+        let code = Random.Shared.Next(0, 1000000).ToString("D6")
+
+        let payload =
+            {
+                Source = "akshare"
+                SourceRevision = "akshare-test/eastmoney"
+                CollectedAt = DateTimeOffset(2026, 9, 21, 8, 0, 0, TimeSpan.Zero)
+                Instruments = [ { Code = code; Name = "收益测试基金"; FundType = None } ]
+            }
+
+        repository().UpsertInstruments(payload, "returns-test-hash")
+        code
+
+    let createFund (initialCash: decimal) =
+        let command =
+            {
+                Name = "收益测试 FOF"
+                InitialCash = initialCash
+                InitialUnitNav = 1.00000000m
+                IsSynthetic = true
+            }
+
+        let key = fixture.Key(sprintf "returns-fund-%s" (Guid.NewGuid().ToString("N")))
+
+        match repository().CreateFund(key, command) with
+        | FundWriteResult.Created fund -> fund.Id
+        | other -> failwithf "unexpected fund creation result: %A" other
+
+    let app () = App.createApplication (repository ())
+
+    let truncateMicroseconds (moment: DateTimeOffset) =
+        let utc = moment.ToUniversalTime()
+        DateTimeOffset(utc.Ticks - (utc.Ticks % 10L), TimeSpan.Zero)
+
+    let insertQuoteOnDate (code: string) (nav: decimal) (navDate: DateOnly) =
+        let revision = sprintf "akshare-test/%O" (Guid.NewGuid())
+
+        let payload: MarketDataNavPayload =
+            {
+                Source = "akshare"
+                SourceRevision = revision
+                CollectedAt = truncateMicroseconds (DateTimeOffset.Now.AddSeconds(-10.0))
+                Code = code
+                Observations =
+                    [
+                        {
+                            NavDate = navDate
+                            PublishedAt = None
+                            Nav = nav
+                            AccumulatedNav = Some nav
+                            DailyReturn = Some 0.0m
+                        }
+                    ]
+            }
+
+        repository().UpsertNavObservations(payload, sprintf "returns-hash/%s" revision)
+
+    let confirmedHolding fundId (code: string) (amount: decimal) (tradeDate: DateOnly) =
+        insertQuoteOnDate code 2.5m tradeDate
+
+        let orderKey = fixture.Key(sprintf "returns-hold-%s" (Guid.NewGuid().ToString("N")))
+
+        let order =
+            match
+                repository().CreateSubscriptionOrder(
+                    orderKey,
+                    fundId,
+                    { FundCode = code; Amount = amount; FeeAmount = 0m },
+                    tradeDate
+                )
+            with
+            | SubscriptionOrderWriteResult.OrderCreated order
+            | SubscriptionOrderWriteResult.OrderReplayed order -> order
+            | other -> failwithf "unexpected holding order result: %A" other
+
+        match
+            repository().ConfirmSubscriptionOrder(
+                fixture.Key(sprintf "returns-confirm-%s" (Guid.NewGuid().ToString("N"))),
+                fundId,
+                order.Id
+            )
+        with
+        | SubscriptionConfirmResult.OrderConfirmed _ -> ()
+        | confirmResult -> failwithf "unexpected holding confirm: %A" confirmResult
+
+        order
+
+    let insertConfirmedOrderWithoutNav fundId (code: string) (tradeDate: DateOnly) (units: decimal) (amount: decimal) =
+        use connection = new NpgsqlConnection(fixture.ConnectionString)
+        connection.Open()
+        use command = connection.CreateCommand()
+
+        command.CommandText <-
+            """
+            INSERT INTO subscription_orders
+                (id, fund_id, fund_code, amount, fee_amount, reserved_total, status, is_synthetic,
+                 submitted_at, trade_date, confirmed_at, confirmed_units, confirmed_invested_cash,
+                 confirmed_residual_cash)
+            VALUES
+                (@id, @fund_id, @code, @amount, 0.00, @amount, 'confirmed', false,
+                 now(), @trade_date, now(), @units, @amount, 0.00)
+            """
+
+        let idParameter = command.Parameters.Add("id", NpgsqlTypes.NpgsqlDbType.Uuid)
+        idParameter.Value <- box (Guid.NewGuid())
+        let fundParameter = command.Parameters.Add("fund_id", NpgsqlTypes.NpgsqlDbType.Uuid)
+        fundParameter.Value <- box fundId
+        let codeParameter = command.Parameters.Add("code", NpgsqlTypes.NpgsqlDbType.Text)
+        codeParameter.Value <- box code
+        let amountParameter = command.Parameters.Add("amount", NpgsqlTypes.NpgsqlDbType.Numeric)
+        amountParameter.Value <- box amount
+        let unitsParameter = command.Parameters.Add("units", NpgsqlTypes.NpgsqlDbType.Numeric)
+        unitsParameter.Value <- box units
+        let dateParameter = command.Parameters.Add("trade_date", NpgsqlTypes.NpgsqlDbType.Date)
+        dateParameter.Value <- box tradeDate
+        command.ExecuteNonQuery() |> ignore
+
+    let getReturns (fundId: Guid) =
+        PersistenceTestHelpers.invoke
+            (app ())
+            "GET"
+            (sprintf "/api/funds/%O/returns" fundId)
+            [ "Authorization", "Bearer test-token" ]
+            ""
+
+    let pointOn (date: string) (body: string) =
+        use document = JsonDocument.Parse(body)
+
+        document.RootElement.GetProperty("points").EnumerateArray()
+        |> Seq.find (fun point -> point.GetProperty("date").GetString() = date)
+        |> fun point -> point.Clone()
+
+    [<Fact>]
+    member _.``returns series is empty for a fund without activity``() =
+        let fundId = createFund 10000.00m
+        let status, body = getReturns fundId
+
+        Assert.Equal(200, status)
+        Assert.Contains("\"points\":[]", body)
+        Assert.Contains("\"pending\":false", body)
+        Assert.Contains("\"dataUpdatedAt\":null", body)
+
+    [<Fact>]
+    member _.``external deposits issue units without moving the unit nav or creating profit``() =
+        let fundId = createFund 10000.00m
+
+        match
+            repository().CreateCapitalDeposit(
+                fixture.Key(sprintf "returns-deposit-%s" (Guid.NewGuid().ToString("N"))),
+                fundId,
+                { Amount = 5000.00m; Note = None }
+            )
+        with
+        | CapitalDepositWriteResult.CapitalDepositCreated _ -> ()
+        | other -> failwithf "unexpected deposit result: %A" other
+
+        let status, body = getReturns fundId
+        Assert.Equal(200, status)
+
+        let today = ConfirmationPolicy.tradeDateFor DateTimeOffset.UtcNow
+        let point = pointOn (today.ToString("yyyy-MM-dd")) body
+
+        Assert.False(point.GetProperty("pending").GetBoolean())
+        Assert.Equal("15000.00", point.GetProperty("totalAssets").GetString())
+        Assert.Equal("15000.00", point.GetProperty("netExternalFlow").GetString())
+        Assert.Equal("0.00", point.GetProperty("cumulativeReturn").GetString())
+        Assert.Equal("1.00000000", point.GetProperty("unitNav").GetString())
+
+    [<Fact>]
+    member _.``returns series revalues holdings on later nav dates``() =
+        let fundId = createFund 10000.00m
+        let code = seedInstrument ()
+        let tradeDate = DateOnly(2026, 9, 15)
+        let _ = confirmedHolding fundId code 250.00m tradeDate
+        insertQuoteOnDate code 3.0m (DateOnly(2026, 9, 16))
+
+        let status, body = getReturns fundId
+        Assert.Equal(200, status)
+
+        let first = pointOn "2026-09-15" body
+        Assert.Equal("10000.00", first.GetProperty("totalAssets").GetString())
+        Assert.Equal("0.00", first.GetProperty("cumulativeReturn").GetString())
+        Assert.Equal("1.00000000", first.GetProperty("unitNav").GetString())
+
+        let second = pointOn "2026-09-16" body
+        Assert.False(second.GetProperty("pending").GetBoolean())
+        Assert.Equal("10050.00", second.GetProperty("totalAssets").GetString())
+        Assert.Equal("50.00", second.GetProperty("cumulativeReturn").GetString())
+        Assert.Equal("1.00500000", second.GetProperty("unitNav").GetString())
+
+    [<Fact>]
+    member _.``held instrument without a valuation nav is pending and never zero filled``() =
+        let fundId = createFund 10000.00m
+        let code = seedInstrument ()
+        let tradeDate = ConfirmationPolicy.tradeDateFor DateTimeOffset.UtcNow
+        insertConfirmedOrderWithoutNav fundId code tradeDate 100.00000000m 250.00m
+
+        let status, body = getReturns fundId
+        Assert.Equal(200, status)
+        Assert.Contains("\"pending\":true", body)
+        Assert.Contains("\"totalAssets\":null", body)
+        Assert.Contains("\"holdingsValue\":null", body)
+        Assert.Contains("\"cumulativeReturn\":null", body)
+
+        let point = pointOn (tradeDate.ToString("yyyy-MM-dd")) body
+        Assert.True(point.GetProperty("pending").GetBoolean())
+        Assert.Equal(JsonValueKind.Null, point.GetProperty("totalAssets").ValueKind)
+        Assert.Equal("9750.00", point.GetProperty("cash").GetString())
+
+    [<Fact>]
+    member _.``returns request for an unknown fund is not found``() =
+        let status, body = getReturns (Guid.NewGuid())
+        Assert.Equal(404, status)
+        Assert.Contains("FUND_NOT_FOUND", body)
diff --git a/tests/FundLab.Web.Tests/ChartTests.fs b/tests/FundLab.Web.Tests/ChartTests.fs
index cede2d2..0382b0a 100644
--- a/tests/FundLab.Web.Tests/ChartTests.fs
+++ b/tests/FundLab.Web.Tests/ChartTests.fs
@@ -21,3 +21,50 @@ module ChartTests =
         Assert.Equal(1.0, points[1].y)
         Assert.Equal(0.4, points[2].y)
         Assert.Equal("2026-01-03", points[2].navDate)
+
+    [<Fact>]
+    let ``series points keep the shared date axis and normalize each series`` () =
+        let dates = [ "2026-01-01"; "2026-01-02"; "2026-01-03" ]
+
+        let values =
+            [
+                "2026-01-01", "100.00"
+                "2026-01-02", "150.00"
+                "2026-01-03", "125.00"
+            ]
+
+        let points = Chart.seriesPoints dates values
+
+        Assert.Equal(3, points.Length)
+        Assert.Equal(0.0, points[0].x)
+        Assert.Equal(0.5, points[1].x)
+        Assert.Equal(1.0, points[2].x)
+        Assert.Equal(0.0, points[0].y)
+        Assert.Equal(1.0, points[1].y)
+        Assert.Equal(0.5, points[2].y)
+        Assert.Equal("150.00", points[1].value)
+
+    [<Fact>]
+    let ``series points skip missing dates instead of filling zero`` () =
+        let dates = [ "2026-01-01"; "2026-01-02"; "2026-01-03" ]
+
+        let values =
+            [
+                "2026-01-01", "100.00"
+                "2026-01-03", "125.00"
+            ]
+
+        let points = Chart.seriesPoints dates values
+
+        Assert.Equal(2, points.Length)
+        Assert.Equal(0.0, points[0].x)
+        Assert.Equal(1.0, points[1].x)
+        Assert.Equal("2026-01-03", points[1].label)
+
+    [<Fact>]
+    let ``a single point is centered and keeps no line`` () =
+        let points = Chart.seriesPoints [ "2026-01-01" ] [ "2026-01-01", "1.00000000" ]
+
+        Assert.Equal(1, points.Length)
+        Assert.Equal(0.5, points[0].x)
+        Assert.Equal(0.5, points[0].y)