Change YTD for a data sheet showing statistics to update to the new year statistics

Hi

I have spreadsheet that has one tab that counts data from the other pages in the spreadsheet for reporting.
What I am trying to do is have a date that I can change from 2011 to 2012 and have the reporting sheet change the data on the report to the next year.

I know that this is probably simple but cant see to find how to do it, any suggestions?


thanks
Steph