VBA代码 - 编译错误：参数数量错误或属性分配无效

Question

我在编写VBA代码时非常陌生。试图编写一个简单的NPV函数来计算初始投资的8个现金流的净现值。继续得到＆＃34;编译错误：错误的参数数量或无效的属性赋值＆＃34;消息，并不知道如何解决它或它意味着什么。以下是我试图写的代码：

Sub npv()`
Dim discrate As Double
Dim cashflows(0 To 8) As Double
Dim npval As Double
discrate = 0.1
cashflows(0) = -8000
cashflows(1) = -1000
cashflows(2) = -500
cashflows(3) = 2800
cashflows(4) = 3000
cashflows(5) = 3500
cashflows(6) = 3000
cashflows(7) = 2700
cashflows(8) = 3000
npval = npv(discrate, cashflows)
End Sub