And engine manufacturers have been developing more fuel-efficient models.

Multinational automakers have struggled in China to keep up with the public's growing appetite for fuel-efficient models.

The 10 most fuel-efficient models, they pointed out, account for less than 2 percent of sales.

Ford needs the highly fuel-efficient models to raise its overall corporate average fuel economy and meet higher Federal standards for 1990 models.

Over a longer period, a bigger response is expected as additional people replace their cars with more fuel-efficient models.

With fewer fuel-efficient models to offer to consumers, sales began to slide.

As they replaced their cars and chose more fuel-efficient models, demand would decline by a maximum of 10 percent, he said.

Dealers in parts of the country are again reporting waiting lists for the fuel-efficient model, even though Toyota has doubled production from last year.

The 747-400 is a fuel-efficient model with six-foot winglets that reduce drag.

Learn how Cadillac changed course to address buyers' demands for smaller more fuel-efficient models.