The Fed is setting a floor underneath bond markets, says B. Riley FBR's Grant
The stock market bulls continue to climb the wall of worry. The Dow and S&P 500 are up more than 35% since the March lows. The Nasdaq is up more than 45 percent, but a rising number of coronavirus cases could threaten the economic recovery. Mark Grant, chief global market strategist at B. Riley FBR, joins "Squawk Box" to discuss.