IMPEACH BUSH

(CBS) The national average price for a gallon of regular gasoline is $3.18, according to the latest Lundberg Survey. As CBS News correspondent Randall Pinkston reports, that is the highest average cost per gallon ever in the United States – even adjusting for inflation.

These days, every trip to the gas station is an experience in sticker shock. A gallon of regular gas costs $3.24 in New York. It's $3.45 in Milwaukee, and $3.59 in Chicago.

This weekend alone, from Friday to Sunday, the average price of gas went up another 5 cents per gallon.

A gallon of mid-grade gasoline averaged $3.29, and premium cost $3.40, according to the latest Lundberg Survey of seven-thousand gas stations across the country.

The price hikes are giving oil companies another banner year. First quarter profits for Exxon-Mobil totaled nearly $9.3 billion. Royal Dutch Schell picked up more than $6.9 billion. The number was $4.7 billion for Chevron.

In a December interview with CBS News, Shell's president defended the industry's high profits.

"The profits are high because the crude price is high, and the cost of producing that crude has not materially changed," John Hofmeister said. "Future investments cost more money."

Oil executives downplay the amount of fuel that can be produced from home grown sources like ethanol.

"I think independence is naive," Hoffmeister told CBS News.

U.S. inventories are at record lows for the pre-summer season – a sure fire formula for higher prices in the future. But many consumers are hurting right now.

To cope with climbing prices, commuters like Denise von Wilke are looking for every possible way to save. She drives more slowly and car pools with a co-worker for her 47-mile trip to work.

Von Wilke also uses the Internet to find bargains. She says she can find the lowest gas prices in all of New Jersey from her desk.

Across the country, the lowest price for regular fuel was $2.87 in Charleston, South Carolina, and the highest was in Chicago at $3.59 a gallon, according to the Lundberg Survey.

Higher fuel costs are driving many Americans to mass transit. The American Transportation Association reports more than 10 billion trips on trains and buses last year – the highest use of public transportation in 49 years.

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