I've used the immediate-If (IIF) quite a bit, as it was one of my most-used functions back in the days of DOS-based FoxPro. (Yes, Access stole it from FoxPro when...

Good point, Wayne. I had forgotten that there is a definite difference between ROWS and RANGE, despite the similar syntax.

I agree with SimonC, the RANGE clause is the better solution to the Running Total problem for read operations.