Here is an article written by an independent thinktank on public policy initiatives called oddly enough, The Independent Institute
“Making Sense of High Housing Prices” discusses the fact that once governments started adopting land use and urban growth controls, prices began to climb.
Economists Edward Glaser of Harvard and Joseph Gyourko of the University of Pennsylvania studied the effect government restrictions have on housing prices in a number of markets around the country. They found that 90 percent of the difference between physical construction cost and the price of new homes could be attributed to government restrictions on building. Only 10 percent of the difference was due to intrinsically scarce land.