I can't figure out why I am getting this error or how to correct it, any thoughts? TThe error is occuring in the line: 
If Range("PaymentAmount").Offset(i, 0) = "Cash" Then
Sub Calculation()
    Dim r As Range, CashAvg As Double, CheckAvg As Double, CreditAvg As Double
    Dim CashSum As Double, CashCount As Integer, CheckSum As Double, CheckCount As Integer, CreditSum As Double, CreditCount As Integer

    Set r = Range(Range("I2"), Range("I2").End(xlDown))
    
    
With ThisWorkbook.Worksheets("Problem3")
    For i = 1 To r.Rows.Count
        If Range("PaymentAmount").Offset(i, 0) = "Cash" Then
            CashSum = CashSum + Range("I").Offset(i, 1)
            CashCount = CashCount + 1
        ElseIf Range("I").Offset(i, 0) = "Check" Then
            CheckSum = CheckSum + Range("I").Offset(i, 1)
            CheckCount = CheckCount + 1
        ElseIf Range("I").Offset(i, 0) = "Credit" Then
            CreditSum = CreditSum + Range("I").Offset(i, 1)
            CreditCount = CreditCount + 1
        End If
    Next i
End With
    
    If CashSum > 0 And CashCount > 0 Then
        CashAvg = CashSum / CashCount
    Else
        CashAvg = 0
    End If
    If CheckSum > 0 And CheckCount > 0 Then
        CheckAvg = CheckSum / CheckCount
    Else
        CashAvg = 0
    End If
    If CreditSum > 0 And CreditCount > 0 Then
        CreditAvg = CreditSum / CreditCount
    Else
        CreditAvg = 0
    End If
    MsgBox "CashAvg = " & CashAvg & "   CheckAvg = " & CheckAvg & "   CreditAvg = " & CreditAvg
        
End Sub