worked like a charm - thanks.

Thanks for the tips - read the article - good info.

My 'solution' involved temp tables, so I'd welcome a faster solution. The example data below has 3 tags and the...

cool thanks - I think a variation of the first reply has got me going. the Date join didn't work, but I added an Identity to the tables and...

I have had to pass this off to someone else who is finishing it, but they have tested your code and tell me it appears to work well and very...

MGD = millions gallons per day - sorry. And that's the flow rate, once I have the average for the time period its easy to convert it to other...

Sorry for the delay - back at it now. Normal flow rates of 0 to 10 mgd. Also there will be lots of data - perhaps a point...

yes, Rolling Window describes it well - never heard of that. Yes, we can limit it to a day, and yes, I should have put 2:02:14 to 3:02:14.

that doesn't sound quite right, though I'm not sure. There doesn't really need to be any parameters. If I assume a table is filled with 86,400 records (1 record per...

Group By Hour would work if I were after the maximum avg flowrate for each hour, with hour being between 1:00 and 2:00, 2:00 and 3:00, etc. But my...