I have the following columns

Apr-2006 Apr 2007
0.00 0.00
0.00 0.00
0.00 331.08
0.00 107.90
0.00 0.00
0.00 970.00
1,134.60 0.00
0.00 2,587.59
5,999.06 16,294.34

I want to work out what the differnece is between 2006 and 2007 by
percentage ie is it a decrease of 25% or increase of 25%, what is the
formula for it?