Here's the thing about gas prices: They're high.
This year, they were so high that they set a record -- Americans will spend more on gasoline in 2012 than in any other year. The yearly national average price will be around $3.63 per gallon, according to GasBuddy.com.
It breaks a record that held the top spot for only one year -- 2011 had an average price of $3.51, or 72.6 cents per gallon higher than the bargain-basement days of 2010.
Of course, there is this statistical caveat: Gas prices theoretically could plummet so severely in these last few weeks that the record-setting average is no longer record-setting. But prices would have to fall to $2.35 per gallon and stay there -- and if that happens, chances are society has bigger problems than gas prices.
The high prices have driven more cars from the road and had a ripple effect on the convenience stores that use the lure of gasoline to sell chips and soft drinks. Here in Pennsylvania, the effects can be especially acute since the average state gas price has been above the national average -- and it was the uncertainty surrounding the fate of several Philadelphia refineries that contributed to the year's rising prices.
In fact, gas prices in Pennsylvania have consistently trended higher than the national average -- in part because of a state tax on gas of about 50.7 cents per gallon, said Gregg Laskoski, senior petroleum analyst at GasBuddy.com.
The average state tax nationwide is about 40 cents per gallon, but Pennsylvania's dime-sized lead on that is nothing compared with Connecticut, which has the highest tax in the country at 70 cents per gallon.
In response to high gas prices, drivers have been saving money by driving less.
In Pennsylvania, the drop in miles driven was even more severe, 2.1 percent, or about 181 million fewer miles. Drivers on the state's rural roads registered a 2.5 percent decrease, while drivers on urban roads had an estimated drop of 1.7 percent.
In the most recent traffic volume trends report, the U.S. Department of Transportation noted year-over-year travel in September fell by 1.5 percent -- or a loss of about 3.6 billion miles. Those miles lost are enough to travel from the Earth to the moon about 15,000 times. (The gasoline costs for those trips? Don't ask.)
Fewer miles driven means fewer trips to the gas station, which is believed by experts to be a major factor behind a noticeable drop in convenience store traffic. In the third quarter, consumer traffic through convenience stores fell 2.1 percent, according to market research firm the NPD Group.
Although consumers made fewer trips to the convenience store, they spent more when they were there -- the average amount spent in a convenience store trip increased 2.5 percent during those same three months, and it wasn't the nation's run on Twinkies that was to blame.
"The $3 mark is where we see behavioral changes," said David Portalatin, a convenience store analyst with the NPD Group. "We change our commuting patterns, and we may normalize around that new price point, but I'm not sure we're there yet."
Stores that have attractions beyond gasoline -- like a made-to-order sandwich bar, or a Redbox video rental machine -- have somewhat inoculated themselves from the drop in business, said Mr. Portalatin.
On a national scale, two events from the past year were cited as major causes of the record-setting average: a refinery fire in California and Hurricane Sandy's disruption of production along the East Coast.
California's fire sent prices rising dramatically in that state, especially since the state's stricter environmental standards for fuel prevent motorists from using gas acceptable in other states. When the fire caused supplies to drop, some parts of California consistently registered gasoline at $4.70 per gallon.
Closer to home, the damage wrought by Hurricane Sandy in early November was seen in the days immediately following the East Coast storm. In the week before the hurricane, refineries along the East Coast -- including those in Philadelphia -- were operating at 81 percent, according to the Department of Energy.
One week later: 58.5 percent.
"The images on the evening news, of people standing and waiting to get gas in New York, should how vulnerable our system is," said Mr. Laskoski.
The East Coast refineries have started to stabilize since then, with the most recent weekly figures measuring the output at 77.1 percent.
Uncertainty clouding the refineries near Philadelphia also were a factor this year. One was idled until it was purchased by Delta Airlines in April to use for jet fuel supplies. Another idled operation called the Marcus Hook facility has been resurrected as a processing plant for products produced by natural gas extracted from the Marcellus Shale. Other Philadelphia refineries have hinted at plans to use shale gas at their facilities, either for processing gas-related products or as their own power source.
Between now and Christmas, Mr. Laskoski expects prices to move incrementally lower -- the end of the fourth quarter is typically a tempered one at the pump, he said, and output should continue to increase as more refineries recover from the storm's losses.
But consumers should expect prices to rise after the New Year's Eve ball drops, he said. The price increases should become particularly noticeable in mid-February and through March and April as conversions to different seasonal blends always force a price increase.
Gas prices have become a minor discussion point in fiscal cliff negotiations in Washington, said Mr. Laskoski, with some legislators proposing an increase in the federal gas tax, which is currently 18.4 cents per gallon.
But after this year, a gas-tax increase is not the best way for a politician to win hearts and minds, he said.
"There's not widespread support for that," he said.