We know that formation though still depressed is running well ahead of net construction.

FORBES: Housing in 2013

New construction has produced a glut of homes, and net rental yields (after maintenance and letting costs) have been driven down to 2%, far below the 7% mortgage rate.

ECONOMIST: Are Australia's economic batteries running low?

Three billionaires in Spain fell off the list that way, and the net worths of six other Spaniards involved in construction and real estate got pummeled.

FORBES

Private residential construction companies, including remodelers, posted an adjusted net profit margin of nearly 4 percent in 2011, following flat margins in 2010 and -1 percent margins in 2009, Sageworks data shows.

FORBES: Residential builders see improved profitability

Since 2003, housing-related industries have accounted for only 4% of the 7 million in net new jobs (including residential construction, mortgage brokers and Realtors).

FORBES: Malpass: 'Sturdy, Not Fragile'