Consumers, possibly reassured by falling gasoline prices, returned to buying large sport utility vehicles in a big way last month. But the impact of the October sales results should be tempered by the fact that the month is being compared with October 2005, which was far from typical.

A year ago, October was "coming off big employee discounts offered by car manufacturers that summer, Hurricane Katrina and $3 a gallon gasoline. All these were historic issues, so its tough to make comparisons," said Rebecca Lindland, associate director of the automotive group at Lexington, Mass.-based research firm Global Insight.

Nevertheless, a look at last month's sales results shows big gains for larger SUV models. Ford's all-new Expedition saw a 27.4 percent increase for October compared with the year-ago month . Cadillac's Escalade enjoyed a 136.2 percent increase and Chevy Suburban sales were up 63.7 percent.

All those are completely new models, reinforcing the theory that, in a highly competitive sales market, American car buyers will turn to the newest models and shun products that have only been around for as little as a year or two.

For instance, Ford's Explorer, just redone for the previous model year, saw sales fall by 21.2 percent in October and sales of the Hummer H3, which also appeared on the scene last year, were off by 8.5 percent.

While SUV sales as a group were hot, sales of small cars that had been hot were not last month. Sales of the Chevrolet Cobalt, for example, plunged 45.2 percent from a year ago. The Chevy HHR was down 31.7 percent, the Chrysler PT Cruiser slipped 12.4 percent, Honda Civic fell 10.7 percent, Hyundai Accent was off 29.6 percent and Mazda3 declined 27.4 percent. Internet inquiries about small cars also tailed off.

"We've never thought here that consumers would move to small cars in large numbers," Ms. Lindland said. "Really, consumers have never left SUVs. While it's true that the sale of mid-sized SUVS have gone down significantly, the sales of crossovers have been quite good.

"For years, we have had people who have purchased SUVs just because they want them and not because they need them. ? When gas is under $2 a gallon, you buy whatever you want, regardless of what you need. But when you start getting into $70, $80, and $100 visits to the gas station, that's when you evaluate carefully just what you really need."

Ms. Lindland said Global Insight has found that people who merely want an SUV are choosing crossovers, while people who need to go off-road or who need cargo capacity are choosing SUVs.

As for small cars, she said. "All things being equal, Americans will still buy the largest vehicle that they can buy," Ms. Lindland said.