I should be able to create query with "relative" date values, such as "today" or "this month" or "this year". Then, those dates should allow "offsets" such as "minus 1" or "minus 7" etc.  

So, when I query my data, I could say for example: "include all gifts given between today and today minus 3"

This would let me automate reports that always include transactions in the given range, without having to manually update them every time.  

This is standard in most databases (such as Oracle, Postgres, etc.)