Following Sara Eisen’s CNBC report on the latest retail market trends, Morning Joe’s Mike Barnicle provides a simple key to understanding the state of the U.S. economy: “You want a great index on how to read the American economy? Go by Home Depot parking lots—if they’re full, things are getting better, and if they’re half empty, things are going down.” Watch the conversation on the current differences in performance between Walmart and Home Depot here. Only on MSNBC.