NEW YORK — Gasoline across the U.S. is cheaper after a week of rapid price declines. But it still isn't cheap.

The national average for a gallon of gas has dropped 13 cents in the past week to $3.625. That's the biggest weekly decline since the seven-day period ended Nov. 28, 2008, according to Oil Price Information Services analyst Fred Rozell.

Falling oil prices, rising supplies of gasoline and a switch by refiners to cheaper winter blends of gas have contributed to lower pump prices.

But gas is still more expensive than it's ever been for this time of year. The previous record for Oct. 23 was last year's $3.46 per gallon.

Rozell says gas has averaged $3.65 so far this year, 10 cents above the record set in 2011.

OPIS surveys about 120,000 gas stations each day. Among the latest findings:

The most common price posted on signs around the country is $3.499 per gallon, down 10 cents from last week.

Prices at the cheapest 1 percent of stations average $3.129 per gallon, compared with $4.645 at the most expensive 1 percent. The spread of $1.50 per gallon is significantly higher than the $1.05 per gallon a year ago.

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Nearly 10 percent of stations across the country are selling gas for more than $4 per gallon, even with the latest declines. A year ago, only about 1 percent of stations were above $4.

Just around 3 percent of stations are selling gas for less than $3.25. A year ago, 12 percent were under $3.25.

High prices on the coasts explain much of the differences. California hit a record of $4.67 per gallon on Oct. 8 when gas supplies ran short because of refinery and pipeline problems. The state average has dropped 31 cents since, but is still 50 cents more than last year.