Former Fed chair Alan Greenspan says his biggest concern is inflation, even if it hasn't emerged yet

Former Federal Reserve Chairman Alan Greenspan joins 'Squawk on the Street' to discuss his views on the U.S. economy. "If anything we are underestimating the size of the budget deficits down the road. I would say all and all my major concern is inflation. It obviously hasn't emerged in any significant way yet but that's where the problems lie and hopefully we'll get new insight on the virus," Greenspan said.