After a month-long rally that repeatedly pushed oil prices to new highs, the cost of a barrel slumped for the fourth day in a row, dropping by nearly $2 to below $44.

Even with the declines, the price remains more than $10 above that of a year ago, and is above last month's highs -- and the impact is still rippling through the economy.

Analysts cited a variety of factors for yesterday's decline, including increased production in Iraq, where pipelines had previously been damaged by attacks. But others said that the drop reflected the market's realization that speculators had driven prices too high.

"Sanity and reason have prevailed over the maddening crowds," said Tom Kloza, senior analyst at the Oil Price Information Service in Lakewood, N.J. "It was just a sense of reason today."

Still, Kloza and other analysts cautioned that prices could easily change direction again, particularly if supplies are disrupted in Iraq or elsewhere.

On the New York Mercantile Exchange, benchmark U.S. crude oil for October delivery closed at $43.47 per barrel, down $1.74 from Tuesday's close. The price has declined nearly 11 percent from last Thursday's high of $48.70.

The still-high prices have battered some businesses while boosting the oil companies. The Federal Reserve blamed high oil prices for a recent sharp slowdown in the economy, but also anticipated that prices would ease.

The transportation sector has been especially hard hit as the cost of jet and diesel fuel has increased.

Truckers have passed along added costs to customers, hitting the manufacturing industry the hardest because it relies heavily on the transportation of goods. Airlines have suffered mounting losses as they are unable to pass along increasing fuel costs to consumers because of fierce competition.

Yesterday, executives from the nation's largest air carriers sent a letter to the Senate Commerce Committee asking for a hearing on the impact of high oil prices on the transportation industry, and for consideration of opening the Strategic Petroleum Reserve as a way to lower prices.

On the campaign trail in Iowa this week, Vice President Cheney said the reserves would only be opened in case of an emergency, such as a disruption that causes the loss of 5 or 6 million barrels a day in imports. The U.S. last week imported about 10.4 million barrels of crude oil per day, according to the American Petroleum Institute, an industry group.

For oil companies, higher oil prices have translated into fatter profits. The Royal Dutch/Shell group, the world's third-largest publicly traded oil company, saw its profit increase last quarter by 54 percent from the same quarter last year, to $4 billion.

In an unusual twist, the record run-up in oil prices in the past month has not spilled over to the gas pump.

In fact, gas prices have dropped slightly -- averaging about $1.88 for a gallon of regular yesterday, according to a AAA auto club survey -- though they remain much higher than last year. The reason is that gasoline reserves remain high thanks to refineries producing at or near capacity, more than satisfying demand from drivers.

Analysts yesterday were divided about where oil prices would go next. Some said they had no idea and that the market would be driven by world events that affect the supply of oil.

"It remains on a hair trigger," said Michael Urban, an analyst with Deutsche Bank in New York. "If you hear that a pipeline is blown up in Iraq, prices will be right back up there."

Analysts and traders have attributed the steep climb in the past month to world production running near capacity while demand has been increasing in China and elsewhere. They feared that any disruption to production caused by terrorism or unrest could lead to an oil shortage.

The pressure on prices has come from several directions recently: concern over a presidential recall vote in oil-rich Venezuela earlier this month; fighting in Najaf, Iraq, where rebels repeatedly threatened to disrupt oil production; and concerns about an ongoing dispute between the Russian government and its largest oil exporter, Yukos Oil.

Each of those concerns has eased in recent days, analysts said.

But some warned that prices could still hit -- or surpass -- $50 a barrel.

"We're seeing some relief in the short term here," said Gerald A. Taylor, a principal of the Brattle Group, a consulting firm in Cambridge, Mass. "A lot of analysts, myself included, feel like the oil price will stay high and probably turn around again."

Yesterday's retreat came despite new data from the Energy Department that some analysts had thought would send prices higher: a decline in U.S. commercial crude oil inventories. The government reported an inventory of 291.3 million barrels for last week, a drop of 1.7 million barrels from the week before.

Motor gasoline inventories remained steady, despite heavy demand. Analysts had expected to see a decline in those stocks and they said the plentiful supply helped exert downward pressure on oil prices.

The sun sets behind an oil field of Venezuelan state oil firm Petroleos de Venezuela in Cabimas, Venezuela, 300 miles west of Caracas. A man works on the pipelines of the Rumeila oil fields, near the city of Basra in Iraq.