(Pablo Martinez Monsivais/Associated Press)

Mortgage rates followed long-term Treasury yields downward, plummeting to lows not seen in more than a year.

The yield on the benchmark 10-year Treasury bond nosedived nearly 11 basis points (a basis point is 0.01 percentage point) last week, marking its biggest weekly decline in two months. The swoon came on the heels of the cautious tone struck by Federal Reserve Chair Janet Yellen in her remarks before the Economics Club of New York.

Because home loan rates tend to follow the movement of long-term notes, mortgage rates also tumbled.

According to the latest data released Thursday by the Federal Home Loan Mortgage Corp., the 30-year fixed-rate average sank to 3.59 percent with an average 0.5 point. (Points are fees paid to a lender equal to 1 percent of the loan amount.) It was 3.71 percent a week ago and 3.66 percent a year ago. The 30-year fixed rate, which hasn’t been this low since February 2015, has dropped 42 basis points since the start of the year.

The 15-year fixed-rate average plunged to 2.88 percent with an average 0.4 point, its lowest level in almost three years. It was 2.98 percent a week ago and 2.93 percent a year ago. The 15-year fixed rate has not fallen this low since May 2013.

The five-year adjustable rate average dropped to 2.82 percent with an average 0.5 point. It was 2.9 percent a week ago and 2.83 percent a year ago.

“Mortgage rates this week registered the delayed impact of last week’s sharp drop in Treasury yields as the 30-year mortgage rate fell 12 basis points to 3.59 percent,” Sean Becketti, Freddie Mac chief economist, said in a statement.

“This rate marks a new low for 2016 and matches last year’s low in February 2015. Low mortgage rates and a positive employment outlook should support a strong housing market in the second quarter of 2016.”

Not surprisingly with rates falling, mortgage applications were higher, according to the latest data from the Mortgage Bankers Association.

The market composite index — a measure of total loan application volume — rose 2.7 percent from the previous week. The refinance index climbed 7 percent, while the purchase index fell 2 percent.

The refinance share of mortgage activity accounted for 54.5 percent of all applications.

The MBA also reported this week that mortgage credit availability fell slightly last month. The Mortgage Credit Availability Index decreased 0.2 percent to 123.5 in March. A decline in the MCAI indicates lending standards are tightening, while increases point toward loosening credit.

“Administrative changes drove declines in the availability of conventional and super conforming loan programs, and those were partially offset by slightly relaxed lending standards on government lending programs, which includes FHA, VA and [Rural Housing Service],” Lynn Fisher, MBA’s vice president of research and economics, said in a statement.