If you are using the one-to-one model and connecting the donor's one-to-one Account to the Opportunity, you can create a summary rollup field that will sum up all opportunites that are "won" with a close date between 12/31/08 and 1/1/10. You have to hard code the dates. You can't use dynamic dates like "CloseDate = thisYear". But each January 1 just change your rollup formula to...



