Fix average price calculation by only considering BUY transactions (#3125)

* Fix average price calculation by only considering buy transactions

* Update changelog

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Fixed
+
+- Fixed an issue in the performance calculation caused by multiple `SELL` activities on the same day
+
 ## 2.62.0 - 2024-03-09
 
 ### Changed

apps/api/src/app/portfolio/portfolio-calculator-baln-buy-and-sell-in-two-activities.spec.ts

@@ -0,0 +1,166 @@
+import { CurrentRateService } from '@ghostfolio/api/app/portfolio/current-rate.service';
+import { ExchangeRateDataService } from '@ghostfolio/api/services/exchange-rate-data/exchange-rate-data.service';
+import { parseDate } from '@ghostfolio/common/helper';
+
+import Big from 'big.js';
+
+import { CurrentRateServiceMock } from './current-rate.service.mock';
+import { PortfolioCalculator } from './portfolio-calculator';
+
+jest.mock('@ghostfolio/api/app/portfolio/current-rate.service', () => {
+  return {
+    // eslint-disable-next-line @typescript-eslint/naming-convention
+    CurrentRateService: jest.fn().mockImplementation(() => {
+      return CurrentRateServiceMock;
+    })
+  };
+});
+
+describe('PortfolioCalculator', () => {
+  let currentRateService: CurrentRateService;
+  let exchangeRateDataService: ExchangeRateDataService;
+
+  beforeEach(() => {
+    currentRateService = new CurrentRateService(null, null, null, null);
+
+    exchangeRateDataService = new ExchangeRateDataService(
+      null,
+      null,
+      null,
+      null
+    );
+  });
+
+  describe('get current positions', () => {
+    it.only('with BALN.SW buy and sell in two activities', async () => {
+      const portfolioCalculator = new PortfolioCalculator({
+        currentRateService,
+        exchangeRateDataService,
+        currency: 'CHF',
+        orders: [
+          {
+            currency: 'CHF',
+            date: '2021-11-22',
+            dataSource: 'YAHOO',
+            fee: new Big(1.55),
+            name: 'Bâloise Holding AG',
+            quantity: new Big(2),
+            symbol: 'BALN.SW',
+            type: 'BUY',
+            unitPrice: new Big(142.9)
+          },
+          {
+            currency: 'CHF',
+            date: '2021-11-30',
+            dataSource: 'YAHOO',
+            fee: new Big(1.65),
+            name: 'Bâloise Holding AG',
+            quantity: new Big(1),
+            symbol: 'BALN.SW',
+            type: 'SELL',
+            unitPrice: new Big(136.6)
+          },
+          {
+            currency: 'CHF',
+            date: '2021-11-30',
+            dataSource: 'YAHOO',
+            fee: new Big(0),
+            name: 'Bâloise Holding AG',
+            quantity: new Big(1),
+            symbol: 'BALN.SW',
+            type: 'SELL',
+            unitPrice: new Big(136.6)
+          }
+        ]
+      });
+
+      portfolioCalculator.computeTransactionPoints();
+
+      const spy = jest
+        .spyOn(Date, 'now')
+        .mockImplementation(() => parseDate('2021-12-18').getTime());
+
+      const chartData = await portfolioCalculator.getChartData({
+        start: parseDate('2021-11-22')
+      });
+
+      const currentPositions = await portfolioCalculator.getCurrentPositions(
+        parseDate('2021-11-22')
+      );
+
+      const investments = portfolioCalculator.getInvestments();
+
+      const investmentsByMonth = portfolioCalculator.getInvestmentsByGroup({
+        data: chartData,
+        groupBy: 'month'
+      });
+
+      spy.mockRestore();
+
+      expect(currentPositions).toEqual({
+        currentValueInBaseCurrency: new Big('0'),
+        errors: [],
+        grossPerformance: new Big('-12.6'),
+        grossPerformancePercentage: new Big('-0.04408677396780965649'),
+        grossPerformancePercentageWithCurrencyEffect: new Big(
+          '-0.04408677396780965649'
+        ),
+        grossPerformanceWithCurrencyEffect: new Big('-12.6'),
+        hasErrors: false,
+        netPerformance: new Big('-15.8'),
+        netPerformancePercentage: new Big('-0.05528341497550734703'),
+        netPerformancePercentageWithCurrencyEffect: new Big(
+          '-0.05528341497550734703'
+        ),
+        netPerformanceWithCurrencyEffect: new Big('-15.8'),
+        positions: [
+          {
+            averagePrice: new Big('0'),
+            currency: 'CHF',
+            dataSource: 'YAHOO',
+            dividend: new Big('0'),
+            dividendInBaseCurrency: new Big('0'),
+            fee: new Big('3.2'),
+            firstBuyDate: '2021-11-22',
+            grossPerformance: new Big('-12.6'),
+            grossPerformancePercentage: new Big('-0.04408677396780965649'),
+            grossPerformancePercentageWithCurrencyEffect: new Big(
+              '-0.04408677396780965649'
+            ),
+            grossPerformanceWithCurrencyEffect: new Big('-12.6'),
+            investment: new Big('0'),
+            investmentWithCurrencyEffect: new Big('0'),
+            netPerformance: new Big('-15.8'),
+            netPerformancePercentage: new Big('-0.05528341497550734703'),
+            netPerformancePercentageWithCurrencyEffect: new Big(
+              '-0.05528341497550734703'
+            ),
+            netPerformanceWithCurrencyEffect: new Big('-15.8'),
+            marketPrice: 148.9,
+            marketPriceInBaseCurrency: 148.9,
+            quantity: new Big('0'),
+            symbol: 'BALN.SW',
+            timeWeightedInvestment: new Big('285.80000000000000396627'),
+            timeWeightedInvestmentWithCurrencyEffect: new Big(
+              '285.80000000000000396627'
+            ),
+            transactionCount: 3,
+            valueInBaseCurrency: new Big('0')
+          }
+        ],
+        totalInvestment: new Big('0'),
+        totalInvestmentWithCurrencyEffect: new Big('0')
+      });
+
+      expect(investments).toEqual([
+        { date: '2021-11-22', investment: new Big('285.8') },
+        { date: '2021-11-30', investment: new Big('0') }
+      ]);
+
+      expect(investmentsByMonth).toEqual([
+        { date: '2021-11-01', investment: 0 },
+        { date: '2021-12-01', investment: 0 }
+      ]);
+    });
+  });
+});

apps/api/src/app/portfolio/portfolio-calculator.ts

@@ -893,13 +893,10 @@ export class PortfolioCalculator {
     } = {};
 
     let totalInvestment = new Big(0);
+    let totalInvestmentFromBuyTransactions = new Big(0);
+    let totalInvestmentFromBuyTransactionsWithCurrencyEffect = new Big(0);
     let totalInvestmentWithCurrencyEffect = new Big(0);
-    let totalInvestmentWithGrossPerformanceFromSell = new Big(0);
+    let totalQuantityFromBuyTransactions = new Big(0);
-
-    let totalInvestmentWithGrossPerformanceFromSellWithCurrencyEffect = new Big(
-      0
-    );
-
     let totalUnits = new Big(0);
     let valueAtStartDate: Big;
     let valueAtStartDateWithCurrencyEffect: Big;
@@ -1138,9 +1135,21 @@ export class PortfolioCalculator {
         transactionInvestment = order.quantity
           .mul(order.unitPriceInBaseCurrency)
           .mul(getFactor(order.type));
+
         transactionInvestmentWithCurrencyEffect = order.quantity
           .mul(order.unitPriceInBaseCurrencyWithCurrencyEffect)
           .mul(getFactor(order.type));
+
+        totalQuantityFromBuyTransactions =
+          totalQuantityFromBuyTransactions.plus(order.quantity);
+
+        totalInvestmentFromBuyTransactions =
+          totalInvestmentFromBuyTransactions.plus(transactionInvestment);
+
+        totalInvestmentFromBuyTransactionsWithCurrencyEffect =
+          totalInvestmentFromBuyTransactionsWithCurrencyEffect.plus(
+            transactionInvestmentWithCurrencyEffect
+          );
       } else if (order.type === 'SELL') {
         if (totalUnits.gt(0)) {
           transactionInvestment = totalInvestment
@@ -1245,35 +1254,21 @@ export class PortfolioCalculator {
           grossPerformanceFromSellWithCurrencyEffect
         );
 
-      totalInvestmentWithGrossPerformanceFromSell =
+      lastAveragePrice = totalQuantityFromBuyTransactions.eq(0)
-        totalInvestmentWithGrossPerformanceFromSell
-          .plus(transactionInvestment)
-          .plus(grossPerformanceFromSell);
-
-      totalInvestmentWithGrossPerformanceFromSellWithCurrencyEffect =
-        totalInvestmentWithGrossPerformanceFromSellWithCurrencyEffect
-          .plus(transactionInvestmentWithCurrencyEffect)
-          .plus(grossPerformanceFromSellWithCurrencyEffect);
-
-      lastAveragePrice = totalUnits.eq(0)
         ? new Big(0)
-        : totalInvestmentWithGrossPerformanceFromSell.div(totalUnits);
+        : totalInvestmentFromBuyTransactions.div(
+            totalQuantityFromBuyTransactions
+          );
 
-      lastAveragePriceWithCurrencyEffect = totalUnits.eq(0)
+      lastAveragePriceWithCurrencyEffect = totalQuantityFromBuyTransactions.eq(
+        0
+      )
         ? new Big(0)
-        : totalInvestmentWithGrossPerformanceFromSellWithCurrencyEffect.div(
+        : totalInvestmentFromBuyTransactionsWithCurrencyEffect.div(
-            totalUnits
+            totalQuantityFromBuyTransactions
           );
 
       if (PortfolioCalculator.ENABLE_LOGGING) {
-        console.log(
-          'totalInvestmentWithGrossPerformanceFromSell',
-          totalInvestmentWithGrossPerformanceFromSell.toNumber()
-        );
-        console.log(
-          'totalInvestmentWithGrossPerformanceFromSellWithCurrencyEffect',
-          totalInvestmentWithGrossPerformanceFromSellWithCurrencyEffect.toNumber()
-        );
         console.log(
           'grossPerformanceFromSells',
           grossPerformanceFromSells.toNumber()
@@ -1319,11 +1314,10 @@ export class PortfolioCalculator {
             orderDate,
             previousOrderDate
           );
-
-          // Set to at least 1 day, otherwise the transactions on the same day
-          // would not be considered in the time weighted calculation
           if (daysSinceLastOrder <= 0) {
-            daysSinceLastOrder = 1;
+            // The time between two activities on the same day is unknown
+            // -> Set it to the smallest floating point number greater than 0
+            daysSinceLastOrder = Number.EPSILON;
           }
 
           // Sum up the total investment days since the start date to calculate