Banders Bowl?
Divide number of pounds lost by the starting weight.multiply by 100
example lets say u started at 300 and want o loose150lbs to goal
and you have lost 150lbs
150/300*100 = 50% total body weight loss
now we dont want to loose 100% of ourselfs :) so we set our goal .. multiply previous answer by 2 and u get ur goal percentage in this case it would be 100%