Average mortgage rates in the U.S. were mostly unchanged in the latest week, with only the 30-year fixed-rate mortgage average recording a slight decline, according to mortgage-finance company Freddie Mac (FMCC).

"Mortgage rates were little changed from the previous week and remain below levels seen the same time last year, which should provide some help with homebuyer affordability in many markets," Freddie Mac Chief Economist Frank Nothaft said Thursday.

"Recent housing data was better with pending home sales up 6.1% in May and overall construction spending showing a slight improvement with private residential spending now up 7.5% on yearly basis," he added.

For the week ended Thursday, the 30-year fixed-rate mortgage averaged 4.12%, compared with 4.14% a week earlier and 4.29% a year earlier. Rates on 15-year fixed-rate mortgages averaged 3.22%, unchanged from the previous week and down from 3.39% a year earlier.

Five-year Treasury-indexed hybrid adjustable-rate mortgages, or ARMs, on average, were at 2.98%, also unchanged from the previous week, but down from 3.10% a year earlier. One-year Treasury-indexed ARM rates on average were 2.38%, compared with 2.4% the previous week and 2.66% a year earlier.

Write to Anna Prior at anna.prior@wsj.com

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