replacing cell value with previous cell value

I am having a worksheet where first line of the each invoice item will have customer code(A) and invoice no.(B), P.code(C), Qty(D) and Value(E) remaing rows of the invoice data will have only P.code(C), Qty(D) and Value(E).

Is there any way I can replace Customer Code and Invoice no in remaing cells by using any Macro without distrubing the data?

Thanks

Sekhar