The question gets back to the number of homes on the market.  I've noticed more homes available now with the last change in the tax laws. You can buy a home, hold it for a few years, sell it for a profit and pay no tax.  I believe there is a new trend growing to buy and sell to take advantage of the tax laws.  Perhpas these economist and realtors should be discussing the number of sellers who have sold homes multiple times these last few years.  
What is the historic vacancy rate of homes in the area for the last ten years.  That would also be a great indicator.