NEW YORK (AP) -- A sharp decline in the price of oil this month is making gasoline cheaper at a time of year when it typically gets more expensive. It's a relief to motorists and business owners and a positive development for the economy.

Over the past three weeks, the price of oil has fallen by 9 percent to $89 a barrel. That has helped extend a slide in gasoline prices that began in late February. Nationwide, average retail prices have fallen by 27 cents per gallon, or 7 percent, since Feb. 27, to $3.52 per gallon. Analysts say pump prices could fall another 20 cents over the next two months.

The price of oil is being driven lower by rising global supplies and lower-than-expected demand in the world's two largest economies, the United States and China. As oil and gasoline become more affordable, the economy benefits because goods become less expensive to transport and motorists have more money to spend on other things.

The typical U.S. household will spend an estimated $326 on gasoline this April, the equivalent of 7.8 percent of median household income, according to Fred Rozell, an analyst at GasBuddy.com. That's $38 less than last April, when households spent 8.8 percent of their income on gas.

Gasoline prices reached a high this year of $3.79 per gallon on Feb. 27. Last year's peak was $3.94, and it came on April 6; last year's low was $3.22 on Dec. 20. The average price for all of 2012 was $3.63 per gallon. The Energy Department forecasts the 2013 average will be $3.56.

Analysts say there are limits to how far oil and gasoline prices will fall.

Countries in the developing world are still growing fast and pushing world oil demand higher, perhaps to a record this year. And if oil prices fall too far drillers will be forced to cut production to try to stem the decline.