I need to show how far into a month we are at any given time in % form. I
want this to change every day automatically. Example:

Today is day 27 of 31 days in January - 87%

if today was 2/17/10 it would need to show 17/28 or 61%, 12/20/10 would be
20/31 or 65%, and so on for each day throughout 2010 (12/20/10 would be 65%)

Is there a formula or function to do this?

Thanks!
Heather