I have a pivot table set up where you can select a time period and a
geography from a drop down list. The first two columns of my report rank
items by dollar by the geography dollars(column E) and the geographies
competitors dollars(column M). If I change the geogrphy's using the drop
down the data changes and the Rank columns work fine. When I change the time
period, my rank columns do not work and just displays a #DIV/0! The remaning
columns all update accordingly, just the rank columns don't work. Formula
used in the rank columns are below.

=IF(C10<"",RANK(E10,$E$10:$E$2000),"")
=IF(C10<"",RANK(M10,$M$10:$M$2000),"")


Any idea as to why it would work when changing the time period?