NEW YORK (AP) — The price of oil slipped back below $100 a barrel Tuesday as the new head of the U.S. Federal Reserve promised to maintain the central bank's approach to monetary policy.

Meanwhile, the Energy Department provided some estimates of how much the harsh winter has is boosting American's heating bills, particularly for the nearly 3,000 homes in the Midwest and Northeast that use propane for heat.

Benchmark U.S. crude for March delivery fell 12 cents to $99.94 a barrel on the New York Mercantile Exchange. On Monday, oil had its first close above $100 since Dec. 27.

Federal Reserve Chair Janet Yellen said she expects a "great deal of continuity" with her predecessor, Ben Bernanke. She signaled that she supports his view that the economy is strengthening enough to withstand a pullback in stimulus but that rates should stay low to further improve a still-lackluster economy.

The U.S. central bank has embarked on a policy to gradually reduce its stimulus, which has helped shore up a number of financial assets over the past few years, including oil prices.

One reason oil is near $100 is increased demand for heating oil due to this winter's frigid temperatures. Demand for natural gas and propane has soared as well. In a report issued Tuesday, the Energy Department estimated how much Americans will spend this winter to heat their homes:

— Households using heating oil will pay on average 3.4 percent more this winter, or about $2,164. Although the price for a gallon of heating oil will be about 5 cents less than a year ago, homes will consume 5 percent more fuel.

— The average cost for natural gas users will rise nearly 8 percent to $649. In the Northeast, where prices spiked sharply at times, the average bill rises 12 percent to $990.

— Propane users feel the biggest hit. Heating costs for Northeast propane users are estimated to rise 19 percent to $2,316; Midwest households will pay 46 percent more for propane, or $1,942. Propane prices spiked because the cold winter boosted demand, helping deplete supplies that were already below normal following last year's corn harvest.

For U.S. drivers, the recent rise in gasoline prices continued Tuesday. The nationwide average for a gallon of gas rose 1 cent to $3.31, a four-week high. Refineries are starting to undergo seasonal maintenance, which lowers supplies and boosts prices heading into spring.

Brent crude, which is used to set prices for international varieties of crude, gained 22 cents to $108.18 a barrel on the ICE Futures exchange in London.

In other energy futures trading in New York:

— Wholesale gasoline gained 3 cents to $2.75 a gallon.

— Heating oil rose 3 cents to $3.03 a gallon.

— Natural gas jumped 25 cents to $4.82 per 1,000 cubic feet.