The cost of oil dropped in dramatic fashion yesterday, as a stronger dollar and economic jitters helped push crude futures down more than $5 to $136.04 a barrel.

Oil's tumble was the second in as many days, a reverse course after a record-high price last Thursday of $145.85 a barrel — double the year-earlier price — that had triggered record retail gasoline and diesel prices.

Traders sent light, sweet crude for August delivery down $6.23 a barrel at one point, before it ended the day down $5.33 on the New York Mercantile Exchange. Crude has fallen more than $9 this week.

In explaining the fall, some analysts cited concerns that weakening economies will cut into worldwide demand.

"We have strong concerns about the sharp rise in oil prices," the Group of Eight countries said in a statement from their annual summit. "The world economy is now facing uncertainty, and downside risk persists."

Other reasons for the price slump included a rebounding dollar, a reduced threat to U.S. production from Hurricane Bertha and an easing of tensions over Iran's nuclear enrichment program.

Several energy analysts cautioned against getting too excited about crude's downward trend.

"I view this as a two-day or three-day price correction that will be followed by new highs by month's end," said James Ritterbusch, president of a Galena, Ill.-based oil trading advisory company.

Stephen Schork, who writes a newsletter on energy markets, echoed that warning.

"We have seen this movie before. ... Crude weakens a little and the bubble-bears jump in," he said in a note to clients. "We are not going to take the bait."