US Homeownership has declined from 69.2% to 56.6% if you exclude households with negative equity
Via Core logic:
According to the Census, the Q3 2010 homeownership rate was 66.9 percent, down from a peak of 69.2 percent in Q4 2004. The Census definition of homeownership includes homeowners in negative equity. However, homeowners in negative equity are not likely to behave similarly to homeowners with equity, because their financial interest (the equity) has disappeared and has only a small prospect of returning soon given price trends. The lack of equity means upside down homeowners are not likely to maintain and improve their property and are more likely to behave like renters.
An alternative definition of homeownership is to exclude owners with negative equity, which nets the effective homeownership rate. Adjusting for severe negative equity of 25 percent or more reveals that the effective homeownership rate as of Q3 was 62.4 percent or 4.5 percentage points lower than the official rate. Removing all negative equity homeowners reveals an effective homeownership rate of 56.6 percent or over 10 percentage points lower than the official rate.