WASHINGTON — More people bought previously owned homes in November, the third increase in four months after the worst summer season in more than a decade.

Still, economists say it could take years for home sales to return to healthy levels.

Buyers bought homes at a seasonally adjusted annual rate of 4.68 million, the National Association of Realtors said Wednesday. Even with the rise, this year is shaping up to be the worst for home sales since 1997.

Economists say it could take at least two years or longer to return to a more normal level for sales of around 6 million units a year.

“The housing market is still flat on its back, but there are signs that it is starting to pick itself up,” said Mark Zandi, chief economist at Moody’s Analytics. “Even with the improvements we expect, next year will still be a very weak market.”

The housing market is still struggling to recover from a boom-bust cycle which helped trigger a severe economic recession. Home prices have tumbled in most markets and many potential buyers worry that prices could fall further.

The median price of a home sold in November was $170,600.

Zandi said he expects prices will fall another 5 percent from where they are now, hitting a bottom in the summer of next year.