RW is based on a " standard weight" calculated by theoretically taking the weight and length of a species across all locations. Problem is that data base does not exist. Many studies on this and the possible shortcomings with the process. There should really be standard weights by geographic locations. A standard fish in GA is not the same as one in MI. Also a standard weight in March is not a standard weight in Aug or Dec.

Having said that so readers will know to take the results with a grain of salt - RW is still a very good tool !!!