EXCEL 2003

Rows = 165

Goal: Run a macro that will 'check' if a cell is empty (C5). If so,
copy previous cell (C4) into a different cell C11. IF not empty
ignore. Next row. Once it finishes at row 165, end. Column / rows are
static, data is dynamic.

For example (I will have a separate macro for each corresponding
month):

MACRO 1
Month is February. If M5 is empty, copy data from L5 and past in S5.

MACRO 2
Month is March. If T5 is blank, copy data from S5 and past in Z5.

ETC...

If the cell is not empty, ignore.

If there is a better way to do this, please recommend. Thanks.