This year's record-shredding spike in gasoline prices has finally ended, with prices throughout the country falling by more than a penny per day.

And American drivers can thank themselves for the drop.

Shocked by prices that reached $4.11 per gallon nationwide and $4.61 in California, drivers stopped buying as much fuel. That cut the demand for gasoline's raw material, crude oil. Crude prices dropped as a result, taking gasoline prices with them.

Now the nationwide average for a gallon of regular gas is $3.96, 11 cents less than a week ago, according to the AAA auto club. California's average remains substantially higher, at $4.32, but it fell 12 cents in the last week.

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"Consumers have definitely sent a message," said AAA spokeswoman Cynthia Harris.

At a time of year when Americans typically hit the highway on vacation, many are staying home or taking shorter trips. A survey by AAA found 1.3 percent fewer Americans traveled during the July Fourth weekend compared with a year ago.

"This is the first time in a decade we've seen less travel on major holiday weekends," Harris said. "People are saying, 'Instead of taking two major road trips this summer, we'll take one.' "

Gasoline is still not cheap. Even though prices are falling, the national average for a gallon of regular remains $1.06 higher than a year ago. California's average is $1.24 higher.

That helps explain why famously car-loving Americans finally started driving fewer miles.

The country used 3.2 percent less gasoline in the last four weeks than during the same period last year, according to data from the U.S. Energy Information Administration. That followed months of similar decreases. Energy traders, who had been caught up in a historic bull market for crude oil, finally took notice.

"Prices got excessively valued and there was too much bullish enthusiasm," said Tom Kloza, chief oil analyst at the Oil Price Information Service. "It was long overdue for a respite."

Crude oil this spring shattered price records that, when adjusted for inflation, had stood for decades. Oil traded on the New York Mercantile Exchange peaked July 3 at $145.29 per barrel, more than twice what it sold for a year earlier. Then traders began to focus on weak demand and ominous economic news. The price started to slide. It closed Monday at $124.73, down 14 percent from the peak.

Kloza warned, however, that the bulls may start running again. Some of the investors who poured money into oil this spring, using it as a hedge against inflation, may jump in again if the stock market tumbles. And worldwide demand for oil remains strong, even if the United States is using less.

He predicts the nationwide average price for regular gasoline will fall to $3.80, while California's average will slide below $4.

"This is a nice little midsummer interlude," Kloza said.

The oil market remains prone to wild price swings, many driven by momentum and fear. A hurricane roaring through the Gulf of Mexico and shutting offshore oil wells could easily push prices back up, analysts say. So could increased tensions with Iran. And if oil starts rising again, gasoline will follow.

Lester Lave, an economics professor at Carnegie Mellon University, says he can picture oil swinging anywhere between $50 per barrel and $250 - $50 in case of a global recession, $250 if the United States goes to war with Iran.

If gas and oil prices keep falling, they have a long way to go before all Americans would benefit. Lave noted that while upper-income Americans find $4 gas a nuisance, lower- and middle-class Americans have trouble paying to keep the tank full. Even with a substantial drop, many Americans would still have to rein in their driving, Lave said.

"If gasoline prices go back down to $3.50, we're going to find there are still people who can't afford to pay for it," he said.

To check gasoline prices in the Bay Area, go to sfgate.com/maps/gasprices.