Assume the data starts in A2 going down

=AVERAGE(OFFSET($A$2,ROW(1:1)*24-24,,24,))

if you copy it down it will average A2:A25, A26:A49 and so on,
so copy it down 365 rows and that should be it

--
Regards,

Peo Sjoblom

(No private emails please, for everyone's
benefit keep the discussion in the newsgroup/forum)



"Water guy" <Water wrote in message
...
How do I summarize a large data set based on specifiec parameters. For
example, I have a data set of water level measurements recorded at 1 hour
increments for 1 year. I would like to calculated a daily average water
level for each day. Is there a faster way to do this than manually
selected
all of the recordings within each day and individually calculating daily
means. In other words, is there a formula I can use that tells excel to
calculated means for each day?