I’m not sure what just caused this air pocket in the market but these note from the Mortgage Bankers Association (MBA) that hit right at noon must have contributed to the slide:

12:02 MBA says U.S. MORTGAGE DELINQUENCY RATE 4.95 PCT IN Q4, UP FROM 4.67 PCT IN Q3 AND FROM 4.70 PCT IN Q4 2005

12:02 MBA says subprime borrowers more vulnerable to higher interest rates, slower home price gains or price drops

12:01 MBA pushes back forecast for housing market to regain footing to end of 2007 vs middle of year

12:01 MBA says delinquency rates rose in 49 states in Q4; foreclosure inventory rates grew in 44 states

12:01 Late payments rise for all loan types but driven mainly by subprime and FHA loans

12:00 According to MBA, Mississippi, Louisiana, Michigan had highest overall late payment rates across all loan types in Q4

12:00 U.S. Mortgage delinquencies, foreclosures rise in Q4 2006 vs prior quarter and year ago, according to MBA

Here’s an intraday shot of QQQQ with 15 minute bars. Note the volume on the big drop: