The Federal Reserve will probably keep its main interest rate “quite low for quite some time,” possibly until 2016, amid languid economic growth, Boston Fed President Eric Rosengren said. 

“You could easily imagine if we have relatively slow growth in the overall economy, even though it picks up from where we are now, that it could be 2016,” Rosengren, who votes on monetary policy this year, said Tuesday on CNBC television. “You’d certainly need to have growth 3 percent or faster if you’d want to see short-term rates rising at that point.”

The Fed is trying to push down unemployment that stood at 7.2 percent in September and boost the U.S. economy by keeping its target interest rate near zero and by buying $85 billion in bonds each month.

“My expectation is the Fed funds rate is going to remain quite low for quite some time,” said Rosengren, who is a consistent backer of bond buying by the Fed to spur growth.

Fed officials’ median estimate for the benchmark lending rate is just 2 percent at the end of 2016, a year when policy makers expect growth as fast as 3.3 percent, inflation of 1.7 percent to 2 percent, and the unemployment rate at 5.4 percent to 5.9 percent, according to their central tendency estimates released in September.

Policy makers have said they’ll taper the asset purchases once the labor market shows sustainable improvement, and they’ll keep the interest rate low as long as unemployment is above 6.5 percent and inflation isn’t forecast to exceed 2.5 percent.

“I would expect that we would be getting certainly below 6.5 percent, which is the threshold we’ve provided, but my expectation is that we’ll still have a very low inflation rate at that point,” Rosengren said Tuesday. “As a result, we’re not going to need to be in much of a hurry to raise short-term rates.” The Fed’s preferred gauge of inflation, the personal consumption expenditures index, rose 1.2 percent in August.

Gross domestic product growth, which stood at 2.5 percent annualized rate in the second quarter after 1.1 percent expansion in the first, remains below the 3 percent Rosengren said would allow the labor market to return to full employment in “a reasonable time period.”

The economy grew at a 2 percent annualized rate in the third quarter, according to the median forecast of 87 economists surveyed by Bloomberg before Commerce Department figures due Nov. 7.

Rosengren, 56, became president of the Boston Fed in 2007. He has only dissented once from a monetary policy decision when, in December 2007, he favored a more aggressive interest rate cut to shore up a weakening economy. (Bloomberg)