First, you can't use the variable ROW it is a reserved word. change to
RowCount. I simplified the code so it is easy to understand. You don't need
select and you don't need offsets.

RowCount = 1
With Sheets("Data")
Do While .Range("D" & RowCount) < ""
Range("K" & RowCount).Formula = "=H" & RowCount & "-F" & RowCount
Range("K" & RowCount).NumberFormat = "dd h:mm:ss"
RowCount = RowCount + 1
Loop
End With


"Don Doan" wrote:

Hi,
I'm a beginner VB and I'm trying to modify this code so that it would
subtract column H against column F and put the resutl in column K...it should
do that until there is a blank space in column D. I can't seemed to get it
working...it only does H2-F2 and not for all the rows...any idea??

Row = 1
With Sheets("Data")
Range("K2").Select
Do While .Range("D" & Row) < ""
ActiveCell.FormulaR1C1 = "=RC[-3]-RC[-5]"
selection.NumberFormat = "dd h:mm:ss"
Row = Row + 1
Loop
End With