Excel spreadsheet with three column dates

10/11/2012 12/31/2010 8/17/2013
2/25/2013 4/30/2010 7/11/2013
8/15/2012 3/31/2010 2/4/2013
5/25/2012 6/30/2010 2/16/2013
10/15/2012 2/28/2010 3/12/2013
6/21/2012 5/31/2010 2/23/2013
6/28/2012 4/30/2010 2/13/2013


2/17/2010 2/28/2010 10/18/2010

What I need to do is if the dates in the both the first and second columns are older than three years from the date of the third column, a yes next to that row should be inserted. I can sort and extract the ones I need from that.

I'm sure it's simple for you guys--not so much for me.