Tricky function

Originally Posted by daniello

I have a worksheet full of day by day data (6 years of weather stats actually). Does anybody know of a cunning way of getting daily averages for these. They are time based, so maybe there is a reading every 15 mins some days and every 30 mins on other days:

Date Time Temp Press
1/1/01 0:00 10.1 1035
1/1/01 0:15 9.5 1033
1/1/01 0:30 9.3 1033
.
.
.
2/1/01 13:20 18.6 996
2/1/01 13:50 18.8 997

etc

So can I calculate the average temp for the 2/1/01 using a formula that will see each day (with a different number of results for each day) separately, without me physically having to input all the cell numbers.

Many thanks

You could try this, put this in E2 and drag down, format the cell to General

=SUMIF($A$2:$A$600,A2,$C$2:$C$600)/COUNTIF($A$2:$A$600,A2) alter range to your requirements