Sheet Index In Vba

I have the following code which is set to work for individual worksheets. How do I change this code so that the macro works for all worksheets starting from sheet index 10 onwards.

Sub CopyDownFormulae()
Dim rCell As Range
Dim lStop As Long

lStop = Cells(Rows.Count, 12).End(xlUp).Row

For Each rCell In Range("N10:U10").SpecialCells(xlCellTypeFormulas).Cells
Range(rCell, Cells(lStop, rCell.Column)).FillDown
Next rCell
End Sub