Here is a chart of homeownership rates in 2007 and 2014 in Closed Access MSAs and in Open Access areas (here, defined as all areas outside Closed Access and Contagion MSAs).*
Remember, the Closed Access cities are the cities where prices are much higher than any other city and where prices rose more sharply than any other cities during the boom. They also are the only cities where low priced homes systematically appreciated more than high priced homes.**
The housing boom is widely attributed to credit extended to marginal households, so much so that "subprime bubble" and "housing bubble" are sometimes used interchangeably.
Here, I am comparing Open and Closed Access ownership patterns as well as changes over time, from 2007 to 2014. Notice, in the Closed Access cities, middle and lower class households with mortgages owned about 9% of the housing stock. This is the portion of the population that was supposedly driving prices up. All mortgaged owner-occupiers only accounted for about 36% of Closed Access housing units. Even in other parts of the country they only accounted for about 42% of housing units. The difference is that in Closed Access cities, mortgaged homeowners overwhelmingly come from the top end of the income distribution.
It is implausible that working age, middle or lower income households were associated with significant pressures pushing Closed Access prices up. Non-conventional mortgages in Closed Access cities had to be focused on young households with high incomes.
In 2007, just under 9% and 17% of Closed and Open Access housing units were owned by households in the bottom 60% of incomes. By 2014, these numbers had dropped to just under 7% and 14%. So, about a quarter of the pool of working age, middle and lower class mortgaged homeowners had dried up since 2007. Homeownership rates have continued to fall since then.
In many ways, homeownership has collapsed much more than aggregate numbers would suggest. In Closed Access cities, mortgaged ownership is down to 30% of all households (from 36%). In Open Access areas, it's down to 34% (from 42%). In Open Access areas, about 40% of homeownership was unencumbered in 2007. By 2014, nearly half of owner-occupiers were unencumbered.
Total homeownership rates have been stabilized because unencumbered owners or lightly encumbered owners were not hurt as badly by falling equity and have been more likely to keep their homes. Mortgaged ownership has been devastated, both because existing owners were foreclosed on and because many potential new owners are locked out of the market.
* Contagion ownership patterns tend to be similar to Open Access ownership patterns.
**The systematic relative increase of low priced homes also began to appear in Washington, DC, Riverside, CA, and Miami by the end of the boom, because prices in their high end zip codes were rising above $500,000 where further home price appreciation slows down compared to lower price levels. This has nothing to do with credit access.