 Right now in the market, 37% of all the homes that are on the market have had a price drop. Robert Refkin is founder and CEO of real estate company Compass. That's more homes with a price drop in the month of June than any time in the last 10 years. Well, given that, what would the mortgage rate on a 30-year fixed rate mortgage have to drop to, you might wonder, to really set the housing market on fire?