Percent Change in Pivot Tables!

I am working in a pivot table and am unable to display the values as % change from one year to the other. My pivot table is set up with 4 columns, one that displays the state and then the other 3 show total for 2009,2010, and 2011. When I attempt to change the value to % of and use the previous year as the base field then (previous) for the base item all of the values show up as N/A. I attached a sample worksheet. Thanks to anyone in advance, your help is greatly appreciated!

problem.xlsx

bump..help please!

Bump...Anyone?