How to calculate internal rate of return (IRR)?

I have a column in a DataGridView which includes before tax cash flow values. Could someone please help me to calculate the IRR (Internal Rate of Return)?

Here is what I have done so far, but getting an error when trying to calculate the IRR function:

Error: Value of type 'Double' cannot be converted to '1-dimensional array of Double. this error refers to "val" in the IRR function.

Thanks so much for your help! Please consider that, I am new and just start coding VB, thanks !!

What I have tried:

Dim prec As String "###,##0.00"
Dim guess As Double=0.1 For i =0 to DataGridView1.Rows.Count -1
For j =0 to DataGridView1.Rows.Count -1
Dim value(j) As Double
Dim val As Double
value(j) = DataGridView1.Rows(i).Cells(0).Value
value(j)=val
Dim cal As Double = IRR(val,guess) * 100
MsBox("IRR = " & Format(cal, CStr(prec)) & " % ")
Text1.Text=cal
Next
Next

1 Reply

Know the answer? Post it — somebody with the same question will find it here.

Ako Musha8y ago
An alternate solution:
Dim rowCount As Integer = DataGridView1.Rows.Count - 1
Dim guess As Double = 0.1
Dim values(rowCount) As Double
For i As Integer = 0 To rowCount
values(i) = DataGridView1.Rows(i).Cells(0).Value
Next
Dim cal As Double = IRR(values, guess) * 100
MsBox("IRR = " & Format(cal, CStr(prec)) & " % ")
Text1.Text=cal
0