Wild guess
SELECT Minute(YourField)\15 +1 as Interval
,Avg(SomeField) as TheAverage
FROM SomeTable
GROUP BY Minute(YourField)\15 +1
That will group in 4 groups
1 - 00 to 14
2 - 15 to 29
3 - 30 to 44
4 - 45 to 59
If you want 1 to 15, 16 to 30, etc you will need to make a modification to the
expression you are using to calculate interval.
And yes, the \ is correct since I am using integer math to calculate the interval.
John Spencer
Access MVP 2002-2005, 2007-2009
The Hilltop Institute
University of Maryland Baltimore County