How do I use a formula to count the remaining days until the end of the month in Excel?

Using the =DAY(TODAY()) commands I can get the date 2/15/2010 to show that we are on day 15 of the month. I would like the number all the way up to the last day of the month and then stay there. In this example November counted up to 30 days, Dec to 31, Jan to 31, and since today is the 15^th of Feb it is currently on 15. Tomorrow it will be 66. After the 31 I would like it to stop at 31. Is there a possible formula for this?

Month	Days
2009-Nov	30
2009-Dec	31
2010-Jan	25
2010-Feb	15

Yes there is a formula. First, you would need to have a fixed component or refer to a year/month value. Try this for January 2010:

=IF(--TEXT(TODAY(),"yyyymm")>201001,DAY(DATE(2010,2,0)),DAY(TODAY()))

That formula would begin by returning 1 on 01-JAN-2010 and increment by 1
each day up through 31-JAN-2010...then it would stay at 31

February 2010 would be this:

=IF(--TEXT(TODAY(),"yyyymm")>201002,DAY(DATE(2010,3,0)),DAY(TODAY()))

Now, one other thing you can do is take the 201002 numbers and place those in a separate column and then just point to that column in your formulas.

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