Oil prices have dropped about 20 percent in a little more than a month, but that may not mean it's time to put the pedal back to the metal for long recreational drives.

It's true that a weakening economy, a sell-off by speculators and a stronger dollar have broken the momentum that sent crude near $150 a barrel hardly a month ago. But in this case, what goes down may come up once the drop in prices makes fuel consumption more attractive.

Last summer, Americans breezed through once-unthinkable $3-per-gallon gasoline, driving as much as they did in 2006 while starting to choose more fuel-efficient cars, said Mary Novak, managing director of North American Energy Services for Lexington, Mass.-based energy consultancy Global Insight.

"It took $4 gasoline to get people to actually drive less," Novak said Friday, as crude closed down $4.82 at $115.20 on the New York Mercantile Exchange, a 20 percent drop from the record high close of $145.29 on July 3.

That run-up had some analysts predicting oil could rise as high as $200 a barrel this year.

But Lehman Bros. said in a report Friday that the bubble is "almost certainly" over.

"Heavy selling as energy trading the energy -- and broader commodity -- complex has infected once indomitable crude oil," the report said. "Barring a physical disruption that may temporarily spike prices, we judge that oil prices have peaked for the next few years."

Still, Novak said oil prices need to stay in triple digits, with corresponding gasoline prices around $3.60 a gallon, to sustain the decreased demand. Otherwise, demand could rebound, pushing prices back up.

"If we don't continue to drive less, the supply/demand balance will tighten back up," she said.

The national average for a gallon of regular gasoline was $3.84 on Friday, down 28 cents from $4.11 a month ago, according to AAA. Texas' average fell to $3.72 from $3.96 in the same span, and Houston's to $3.69 from $3.94.

Michael Stugotts, a futures broker at Interwoven Capital, said prices could fall back to $100 a barrel, but not much lower. Saudi Arabia, Russia, Venezuela and other major global producers took a liking to $100 oil -- which didn't dent demand -- and could reduce output to keep the three-figure price.

"Prices may go below that for a while, but not for any real period of time," he said. "Make no mistake, they all like $100 oil."

Oil's rapid rise -- $100 to $140 from the first of April to the end of June, and higher through the first few days of July -- left plenty of analysts wondering where the tipping point might be.

Increasing energy thirst in booming economies in China, India and the Middle East overshadowed the weakening U.S. economy and rising inventories, and geopolitics contributed with concerns about Iran's nuclear ambitions and civil unrest in oil-rich Nigeria.

Congress, the Organization of the Petroleum Exporting Countries and some analysts blamed speculators, such as hedge funds and pension funds, for pouring money into commodities as a safe having against inflation and falling stocks.

But the Commodity Futures Trading Commission countered that fundamental supply and demand issues were the "best explanation" for crude's ascent.

And the slumping dollar, further weakened by the Federal Reserve's string of interest rate cuts, drove more foreign investment in commodities said a commodity broker

This week the greenback got some of its mojo back.

The euro fell below $1.50 Friday for the first time in more than five months after European Central Bank President Jean-Claude Trichet said Thursday that economic growth would be weak through September.

"I would say that the dollar has really staged a pretty impressive rebound. It's somewhat tangential to the oil markets, but there appears to be a shift in how the dollar is being looked at," said Addison Armstrong, director of market research for Tradition Energy in Stamford, Conn.

He said $34 billion in foreign funds went into the U.S. Treasury market this week, demonstrating that investors are looking to it as a safe haven "for the first time in a long time."

That faith in U.S. government securities is good for the dollar, he said.

And oil's drop appears to show that the market has finally recognized shrinking demand in the U.S., Europe and other industrialized nations, said James Williams, head of WTRG Economics, an Arkansas-based energy consulting firm.

"The market has realized that, 'Hey, we're not using as much crude oil as we were, particularly in the United States,' " he said. "Our consumption is probably down 4 to 4.5 percent. That's approaching 1 million barrels a day down from last year."