Fewer U.S. homeowners were underwater on their mortgages in the second quarter, helped by an improvement in home prices, data analysis firm CoreLogic said on Wednesday.

There were 10.8 million homeowners who owed more on their mortgages than their home was worth in the second quarter of the year, down from 11.4 million in the first three months of 2012, CoreLogic said.

That accounted for 22.3 percent of properties, down from 23.7 percent. An additional 2.3 million borrowers had less than 5 percent equity in their homes, considered to be near negative equity.

The large number of underwater homeowners — also known as being in negative equity — has raised concerns borrowers could choose to walk away from their homes rather than struggle with burdensome mortgages.

But most underwater borrowers are continuing to pay their mortgages, the report showed. The share of homeowners that were underwater and up to date on their payments was 84.9 percent, up slightly from 84.8 percent in the first quarter.

About 600,000 homeowners returned to positive equity in the second quarter, adding to the 700,000 that were above water in the first quarter.

Negative equity totaled $689 billion, down from $691 billion.

Hard-hit Nevada had the highest share of underwater homeowners at 59 percent. The top five states, which also included Florida and Arizona, accounted for 34.1 percent of the total amount of negative equity.