PORTLAND, Maine — While Maine is the country’s most heavily dependent state on home heating oil, it led other New England states in reducing reliance on this energy source over a recent five-year period, federal figures show.

The U.S. Energy Information Administration says Mainers slashed their heating oil use by 45 percent between 2004 and 2009. Maine was followed by New Hampshire, which cut its heating oil use by 39 percent; Connecticut by 29 percent; Massachusetts 28 percent; Vermont 27 percent and Rhode Island 25 percent.

The reduction in Maine’s fuel oil consumption was an accomplishment that the state’s energy director said wasn’t widely recognized but that is significant given that Maine is the most heavily dependent in the nation on heating oil by percentage of homes that rely on it. Census figures show about 70 percent of Maine homes use heating oil, down from 80 percent in 2000.

Just because a household retains an oil furnace as a central heating system doesn’t necessarily mean the unit is running all the time, state Energy Director Ken Fletcher told the Maine Today Media newspapers.

“The thing that counts is how much oil they’re using,” said Fletcher. “That’s the bottom line.”

In all six New England states, total heating oil consumption between 2004 and 2009 fell 26 percent, from 4.5 billion gallons in 2004 to 3.4 billion gallons in 2009, the most recent year available, according to the federal report. Households led the trend, with consumption down 34 percent during the period.

The decrease is because of conservation and weatherization, switching to other, cheaper fuels such as wood pellets and natural gas, and cutbacks in households that choose to keep the thermostat lower because of a loss of jobs or other economic forces.

Also having an impact is the cost of fuel oil prices. The federal EIA projects record-high average prices this winter, up 10 percent from last year. Maine’s statewide average last week was $3.59 a gallon.

By comparison, the EIA expects propane prices to rise 7 percent, residential natural gas prices to go up 4 percent, and electricity prices to rise 1 percent.