Here's the problem with studies like this sponsored by Bernie Sanders, he goes to Professor Fuddy Duddy and says I need a study done to show such and such here's $1.5 million dollars put up by the let's say the DNC. Professor Fuddy Duddy will write anything you want and to show anything you want. You just have to take these studies with a gain of salt. There is no free lunch, someone pays, always.