public void CalculateDividendYieldForCommonStockTest() { var stockCommon = new CommonStock { symbol = "TEA", lastDividend = 10, parValue = 100 }; var currentDividendCommon = exchangeStock.CalculateDividendYield(stockCommon, 100); var expectedDividendYield = 0.1; Assert.AreEqual(expectedDividendYield, currentDividendCommon); }