How To AVG Values For One Hour Of Five-minute Increments?

Hello all,

I have the following very simple SQL Query:

SELECT TOP (100) AutoNumber, Date, ZNT, SAT, RAT, RH
FROM HV_Values
ORDER BY Date ASC

This shows the top 100 entries for a table (where there is a date entry every 5 minutes). Here's five sample records:

1 12/4/2006 4:12:11 PM 67.13 70.50 71.56 8.23
2 12/4/2006 4:17:11 PM 67.13 70.50 71.56 8.33
3 12/4/2006 4:22:11 PM 67.19 70.69 71.69 8.19
4 12/4/2006 4:27:11 PM 67.19 70.63 71.69 8.18
5 12/4/2006 4:32:11 PM 67.19 70.69 71.75 8.05

What I'd like to do with the sample query above is take an AVG for one hour for the values ZNT, SAT, RAT, RH...like I stated the records are every five minutes in the table, I'd like to create 60 minute AVGs.

Any ideas or sample queries I can work with?

Thank you very much! gad1