Gasoline and home heating fuel costs are continuing to fall with the price of oil, though one industry expert says they won't drop at the same pace, and never have.

Michael Ervin of MJ Ervin & Associates said in an interview last week the price of a barrel of crude oil is only one of four key costs which influence the price of fuel.

He said you can't apply the nosedive in the barrel price straight across to the price at the pumps.

"They are related, but they are not tied at the waste," Ervin said from his office in Calgary.

The price of gas and heating fuel, he said, is like a four-layer cake standing 25 centimetres high. The price of crude oil is one layer, and the refinery charges another, along with the mark-up at the pumps, and taxes.

Ervin said if you take out the layer for crude oil, cut it in half and then slide it back in, the cake still stands at 25 centimetres.

"When the price of crude oil drops, do taxes decrease?"

He said unless the price per barrel continues its free-fall, he suspects the end of the drop in fuel prices is near. On the other hand, he doesn't see anything that would drive them back up right away.

Ervin explained the price of diesel fuel and home heating fuel overcame the price of gasoline a couple of years ago because of the supply in demand curve, with a huge increase in North America for what's known as the family of middle distillates.

Diesel and stove oil are middle distillates, he pointed out.

Prices at the pumps today were hovering round 89 to 90 cents a litre for regular gasoline, the lowest they've been in four years, since December 2004.

The cost of regular gas rose above $1 for the first time in April 2005.

Just last week, the average Whitehorse price was 95.4 cents a litre, according to the weekly survey by MJ Ervin and Associates.

Last July saw the highest price on record, with the average price of gas selling at $1.464 per litre, when a barrel of crude peaked at $145.29 US.

Records show the meteoric rise in the price of crude oil began in 2002, when it lifted off from somewhere around $25 a barrel. It never looked back until a nosedive started during the past summer as the worldwide recession began unfolding.

The price of diesel fuel was lowest today at $1.119 Cdn. It peaked at $1.554 this past summer, and motorists would have to go back to last March to see the price of diesel at this level. It broke the $1 a litre barrier in April 2005.

An informal survey of local dealers this morning showed the price of home heating fuel for an outdoor, above-ground tank on regularly monthly delivery selling at anywhere from $1 a litre to $1.07, including the GST.