I am in Alabama and am getting up to 2 lbs per year. Average is about 1.5. Started with fat heads, Coppernose BG, in April 2000 and stocked the F1's in June. Added threadfin, and Tilapia after first year. Also, feeding from automatic feeders and fertilize on regular basis. The land around the pond is very fertile and has natural occuring limestone
Have been catching some 5 to 5.5 pounders and the lake was shocked early April and they got some 6 pounders up.
Don't know where you are located because from what I have read it makes a difference.
Hope this helps and good luck.