I am having problems with a spreadsheet I am creating. The spreadsheet looks
something like this.

Average Most Recent
2004 2005 2006 2007 all data
12 Months
Jan 1 2 3 0
Feb 4 5 6 0
Mar 7 8 9 0
Apr 10 11 0 0

The formula I am using for the average of all data is
=sumif(B11:E11,"1")/Countif (B11:E11,"1") This formula seems to work.
However, when there is no data I get a #DIV/0! Error. How can I fix this.

Also, I am still not getting a correct formula to retrieve the most recent
12 months of data. Any help would be appreciated. Thanks in advance.