Even so, the mortgage delinquency rate is still above the 1 percent to 2 percent average historical range, an indication that many homeowners still are struggling to make their payments.
Before the housing bust, mortgage delinquencies were running at less than 2 percent nationally. They peaked at nearly 7 percent in the fourth quarter of 2009.
The late-payment rate in the April-June quarter improved in every state, with Arizona posting the biggest annual decline. The state's mortgage delinquency rate was for the quarter was 3.6 percent, down about 42 percent from the second quarter last year.
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California, with a rate of 3.6 percent, and Colorado (2.3 percent) also had steep annual declines in the rate of late payments.
Florida had the highest mortgage delinquency rate in the nation at nearly 9.9 percent, even though it declined about 27 percent from a year earlier.
TransUnion, which draws its data from a sample of 27 million consumer records, anticipates the national mortgage delinquency rate will continue to decline in the third quarter, finishing below 4 percent.
"We're still a long way from what we'd call normal," Martin said.