Exchange traded funds that invest in U.S. homebuilder stocks have easily doubled the return of the S&P 500 in 2012 even though the homeownership rate has dropped to the lowest level in over a decade.

SPDR S&P Homebuilders ETF (NYSEArca: XHB) and iShares Dow Jones US Home Construction (NYSEArca: ITB) are up 26% and 30% year to date, respectively. The S&P 500 has gained about 12%.

The sector ETFs are getting a boost from upbeat homebuilder earnings and signs of improvement in housing data. For example, pending home sales rose about 4% in March to the highest level in about two years. [Builder ETFs Jump on Home Sales]

Still, most economists aren’t looking for a V-shaped recovery in the housing market, but rather a “prolonged bottom,” according to a recent WSJ.com article.

“The good news is that housing construction and home sales appear to have hit a floor,” the newspaper reported. “The problem, of course, is that foreclosures are still a very high share of sales in many of the hardest-hit markets.”

Also, the homeownership rate fell to 65.4% in the first quarter, the lowest level since 1997, Bloomberg News reports.

“Although house prices and mortgage rates have fallen to a level that makes buying preferable to renting, ongoing problems accessing mortgage credit are preventing many households from taking advantage,” said Paul Diggle, property economist with Capital Economics, in the story.

iShares Dow Jones US Home Construction