A FICO survey of North American mortgage lenders found that many are concerned about the potential of another housing crash. Fifty-six percent of lenders surveyed are concerned that an "unsustainable real estate bubble is inflating." FICO Chief Analytics Officer Dr. Andrew Jennings explains that six million homeowners in the U.S. are still underwater on their mortgages, with the average negative equity at 33%. Yet total homeowner equity in the U.S. is at its highest level since late 2007 as home prices soar in many cities. This disparity has lenders tightening their underwriting standards.