Sub TestPPMT()
    Dim PVal, APR, TotPmts, Payment, Period, P, I As Double
    Dim PayType As DueDate
    Dim Msg As String
    Dim Response As MsgBoxResult

    ' Define money format.
    Dim Fmt As String = "###,###,##0.00"
    ' Usually 0 for a loan.
    Dim Fval As Double = 0
    PVal = CDbl(InputBox("How much do you want to borrow?"))
    APR = CDbl(InputBox("What is the annual percentage rate of your loan?"))
    ' Ensure proper form.
    If APR > 1 Then APR = APR / 100
    TotPmts = CDbl(InputBox("How many monthly payments do you have to make?"))
    Response = MsgBox("Do you make payments at the end of month?", MsgBoxStyle.YesNo)
    If Response = MsgBoxResult.No Then
        PayType = DueDate.BegOfPeriod
    Else
        PayType = DueDate.EndOfPeriod
    End If
    Payment = Math.Abs(-Pmt(APR / 12, TotPmts, PVal, FVal, PayType))
    Msg = "Your monthly payment is " & Format(Payment, Fmt) & ". "
    Msg = Msg & "Would you like a breakdown of your principal and "
    Msg = Msg & "interest per period?"
    ' See if chart is desired. 
    Response = MsgBox(Msg, MsgBoxStyle.YesNo)
    If Response <> MsgBoxResult.No Then
        If TotPmts > 12 Then MsgBox("Only first year will be shown.")
        Msg = "Month  Payment  Principal  Interest" & vbNewLine
        For Period = 1 To TotPmts
            ' Show only first 12.
            If Period > 12 Then Exit For
            P = PPmt(APR / 12, Period, TotPmts, -PVal, FVal, PayType)
            ' Round principal.
            P = (Int((P + 0.005) * 100) / 100)
            I = Payment - P
            ' Round interest.
            I = (Int((I + 0.005) * 100) / 100)
            Msg = Msg & Period & vbTab & Format(Payment, Fmt)
            Msg = Msg & vbTab & Format(P, Fmt) & vbTab & Format(I, Fmt) & vbNewLine
        Next Period
        ' Display amortization table.
        MsgBox(Msg)
    End If
End Sub