Do While Excel Macro for calculations - Part 2

Today we'll use the do while Excel macro and complete the VAT and final amout calculations by referring to cells using the row and index numbers..
The code now looks like this:
Sub calculations()
Row = 3
Do While Cells(Row, 1) <> ""
Cells(Row, 4) = Cells(Row, 3) * Cells(Row, 2)
Cells(Row, 5) = Cells(Row, 4) * 0.125
Cells(Row, 6) = Cells(Row, 4) + Cells(Row, 5)
Row = Row + 1
Loop
End Sub