WASHINGTON — Consumer prices in November plunged by the largest amount on records going back 61 years as energy costs posted nearly double the decline of the previous month.

The Labor Department reported Tuesday that consumer prices fell 1.7 percent in November, surpassing the previous record decline of 1 percent set in October. The drop was the largest one-month decline dating to February 1947.

The huge decreases reflect the severe recession gripping the country and raise the pressure for the Federal Reserve to act decisively to guard against a debilitating bout of deflation.

In other economic news, the Commerce Department reported that construction of new homes fell in November by 18.9 percent, the biggest drop in a quarter-century. The steep decline pushed construction down to a seasonally adjusted annual rate of 625,000 homes, the slowest pace on records that go back to 1959.

The Fed wrapped up a two-day meeting Tuesday. Economists expected the central bank to cut the federal funds rate, already at a low of 1 percent, by another half-point in an effort to keep the recession from worsening.