Depends on the thickness of the latex, tension you have it tuned to, how tight your band or o-ring is around the call, etc. Set up right the call should last the season at least. Once I get mine tuned I cut off all the extra latex around the bottom of the o-ring and never pull on it again.
I use thicker latex than most and have light tension on it. The edge of the latex can 'wrinkle' or look like it shows wear but still play fine and in tune.