My vines are of different ages, but most are in the 3 and 4 year range. So it's not feasible to estimate what the increase in production would have been without the severe winter we had here. I lost 3 or 4 newly transplanted vines (who knows if they would have lived under normal circumstances?) And I lost several feet of cordon and sometimes all the cordon on several vines. This is on muscadine vines in southeast Missouri.