copy down formular from the row above

Hi Everybody,

I need to copy down the formular from column C&D from the row above, every row is one week, so the last row is week 52.
The code I have it copy the exact formular from the cell, it is not copy DOWN the formular.

Any help will be appreciate it.

Thanks.

Sub copyFormulaString()
 Dim LastRow As Long
 Dim m_copy As String
 
    m_copy = Range("M1").Value
    
    LastRow = Sheets("Sheet1").Cells(53, "c").End(xlUp).Row
    
    stRow = Sheets("Sheet1").Range("D" & Rows.Count).End(xlUp).Row
        Sheets("Sheet1").Select
        Range(m_copy).Formula = Range("C3").Formula

Hi MarvinP, Thanks for your reply. I can't upload a file.

So here is an example, hope it can explain better.
the week number is in column A,2011 in column B,2012 column C ( B&C) are the ones I need to copy down the formular.
The C6 is in cell "M1"



2011 2012 week on week Cell update to C6
week1 200 100
week2 200 200 100%
week3 200 300 50%
week4 200 400 33%
week5 200 520 30%
week6 200
week7 200
week8 200
week9 200
week10 200
week11 200
week12 200
week13 200
week14 200

I saw that function, it's work computer security reason,I can't upload files to the web site.

Hi OEGO, I used your code and it works, however it is only copy the formular in column C, What should I change to get formular copy down for Column D as well.

what's the "R1C1" mean?
Thanks for your help.

Regards