Countifs to get criteria from a cell reference

We are focusing on Row 16. The formula: =COUNTIFS('Capacity SO'!$C:$C,">=1/24/2011",'Capacity SO'!$C:$C,"<=1/30/2011")

Just start with Column E first. It is possible to make "1/24/2011" E9, so that if I change the date in E9 it will also change the formula to search for values >= to E9?

Attached is the spreadsheet in question.