Existing homeowners now average about $315,000 in equity, which is almost $129,000 more than at the onset of the pandemic in 2020, said Selma Hepp, chief economist for Corelogic.

"The substantial accumulation of home equity for existing homeowners has served as an important financial buffer in times of uncertainty, as some homeowners facing higher costs of homeowners' insurance and taxes and have had to tap into their equity to prevent falling behind on their mortgages," Hepp said in a press release. "As a result, mortgage delinquency rates have remained at historical lows despite the inflationary pressures and higher costs of almost all non-mortgage homeownership-related expenses."

Previously, Corelogic released its monthly Home Price Index, which showed a 0.01 decline in prices month-to-month for July, while the annual gain was 4.3%.

But unlike for the HPI, where all 50 states had year-over-year increases, three states had lower cumulative homeowner equity at the end of the second quarter versus 12 months' prior: Texas (down $2,600), Oklahoma ($7,700 lower), and North Dakota (off by $8,400).

Because of the increased home values, the share of existing mortgagors in a negative equity position continues to slip.

On a quarter-to-quarter basis, the total number of homes in negative equity decreased by 4.2%, to approximately 960,000 homes or 1.7% of all properties with a mortgage. Underwater borrowers are more likely to default on their loan.

Annually, the decline was 15% or 169,000 fewer homes now where the property owner owes more than it is worth.

The three states with the highest share of borrowers in negative equity are Louisiana, 5.6%; Iowa, 4.6%; and Mississippi, 3.9%.

At the other end of the spectrum, the states where fewer than 1% of mortgage borrowers owning more than the home was valued at are California and Nevada at 0.7% and Arizona at 0.9%.