Petchenik worked with DNR's licensing staff to run a query of the automated licensing system to see how many people bought a trout stamp for every year 2004-2008 but stopped buying the stamp after 2008. That total was 2, 268. Those people received a letter to verify their address was still current. The survey design called for 800 of them to get a survey in the mail to fill out and return. The surveys were mailed out the second week of October.