Hi David
I presume you have missed out a column and what you really have is
Date Value MTD YTD
where column B holds the value that you want summed.
If so, cell C2 =B2, cell D2 =B2
In cell C3
=IF(A3="","",IF(MONTH(A3)<>MONTH(A2),B3,C2+B3))
in cell D3
=IF(A3="","",IF(YEAR(A3)<>YEAR(A2),B3,D2+B3))
Copy both formulae down as far as required

Signature
Regards
Roger Govier
>I have created a daily report to track revenue and marketing
> information. This report includes columns titlted
[quoted text clipped - 8 lines]
>
> David Hopper