Calculate monthly, quarterly, and yearly averages from daily data

Dear Excel Geniuses,

I have a column of daily data over many years (ignoring weekends and holidays) and would like to average them in the following monthly format:

Jan 2010, 123
Feb 2010, 456
...
Dec 2010, 789
Jan 2011, 1234
Feb 2011, 5678
...
etc.

Then I would like to compile them in the following quarterly and yearly formats:

Qtr 1, 2010, abc
Qtr 2, 2010, xyz
...
Qtr 1, 2011, def
Qtr 2, 2011, ghi

and
2010, 123
2011, 456
...

Thanks for any help. I want a time series of the averaged data, but am having trouble getting a formula to work.

Thanks much! I was not aware of the "grouping" feature in pivot tables. I was only able to total, average, etc. the data by month, quarter, etc. but this will give me the time series I want.

Thanks again!