How do I use DAverage in Excel?
 

I have a spreadsheet with columns of data on sheet 1. I would like to have
the average of column "U" determined ONLY when the corresponding data in
Column "C" equals a certain value (date value shown as: "2005/01/01")

I would like this average shown on another sheet that I have termed "Summary".

I cannot get this to work.

Somebody please help!