The biggest challenge in today’s real estate market is a lack of housing inventory. How big of a challenge is the housing shortage? Here are what four industry economists are saying on the issue (emphases added):

Mark Fleming, First American’s Chief Economist

“The underlying fundamental issue is an overwhelming lack of supply… The supply of newly constructed homes is also sagging, adding to the supply challenges. Over the last eight years, housing demand has increased by 5.9 million, but the net new number of housing units has only increased by 3.5 million.”

Svenja Gudell, Zillow’s Chief Economist

“Everyone has been talking about tight inventory but I think we are OK calling it a straight up inventory crisis at this point. We just don’t have enough homes.”

Sean Becketti, Freddie Mac’s Chief Economist

“House prices today are higher than they were at the peak in the summer of 2006, near-record-low mortgage rates have boosted housing demand, and sales volume is robust. The spoiler is the lean inventory of houses for sale.”

Lawrence Yun, National Association of Realtors’ Chief Economist

“Listings in the affordable price range continue to be scooped up rapidly, but the severe housing shortages inflicting many markets are keeping a large segment of would-be buyers on the sidelines.”