We've used data from the Energy Information Administration (EIA), which publishes price data weekly on home heating oil in 38 states by dollar-per-gallon before taxes. Unlike natural gas and electricity, home heating oil is provided by independent retailers.

The latest price of home heating oil nationwide is $3.18, unchanged from last week and down eleven cents since the beginning of the season.

EIA's heating oil data is seasonal - from October through March. Here's a look at the series since its inception in 1990.

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The next chart shows a regional breakdown. As you can see, it's extremely volatile.

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Another figure the EIA tracks is the residential oil supply. The chart below shows the minimal changes in residential heating oil supply since 1982.

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The next chart shows the New York Harbor (NYMEX: HO) spot prices going back to 1986.

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