A similar problem - trying to fill a formula down:

I want column D to show the difference between B and C

D2 = C2-B2
D3 = C3-B3
D4 = C4-B4
and so on

I've figured out how to fill STDEV like this:

xlapp.Workbooks(strXlsFile).Worksheets(sn(i)).Rang e _
("F2:F" & lr).Formula = "=STDEV(" & xlapp.Workbooks _
(strXlsFile).Worksheets(sn(i)).Range(xlapp.Workboo ks _
(strXlsFile).Worksheets(sn(i)).Cells(2, 7), _
xlapp.Workbooks(strXlsFile).Worksheets(sn(i)).Cell s _
(2, lc)).Address(0, 0) & ")"

But how do I fill a formula that simply subtracts?

Thanks again...