WASHINGTON — The government said this morning that millions of older Americans who rely on federal benefits will get a 1.7 percent increase in their monthly payments next year.

It’s the third year in a row the increase will be less than 2 percent.

The annual cost-of-living adjustment affects payments for more than 70 million Social Security recipients, disabled veterans and federal retirees.

The government announced the increase today, when it released the latest measure of consumer prices. By law, the increase is based on inflation, which is well below historical averages so far this year.

Congress enacted automatic increases for Social Security beneficiaries in 1975. Until recently, the increases were rarely less than 2 percent.