The Bush administration is extending incentives that make it easier for automakers to meet fuel economy requirements by selling vehicles that can run on corn-based ethanol and other alternatives to gasoline, according to a CNN report on February 19.Congress enacted the program to try to get people to use alternative fuels. The extension covers vehicles through the 2008-model year, the National Highway Traffic Safety Administration (NHTSA) said Feb 18. The program, approved by Congress in 1998, originally covered vehicles from the 1993- to 2004-model years.Critics have called the incentives a failure because most people who buy the dual-fuel vehicles continue to use gasoline instead of the 85-percent ethanol blend that the program was supposed to promote. Now there are only 182 fueling stations that provide ethanol-85 fuel, mostly in the Midwest, according to the government.Automakers have produced 3.4 million dual-fuel vehicles since 1998 when the incentives went into effect. By making the cars, manufactures get a credit against their overall requirements to meet fleet-wide fuel economy standards.Environmentalists have argued that the program should be repealed because it has failed to do what Congress intended since less than 1 percent of the dual-fuel vehicles end up using the alternative fuel, according to CNN.NHTSA, which issues fuel economy standards, acknowledged that the program has not yet achieved significant shifting from gasoline to ethanol-85 fuel. But the agency said it was extending the incentive for another four years "to allow the continued development of dual fuel vehicles" at a time when automakers are stepping up their promotions of the vehicles.