public void DebitInterests() { TransactionManager transactionManager = new TransactionManager(); Account debitAccount = new Account() { Balance = 100, DebitInterestYearly = .02 }; for (int i = 0; i < 365; i++) { transactionManager.ApplyDailyInterest(debitAccount); } Assert.AreEqual(102, Math.Round(debitAccount.Balance, 2)); }