WASHINGTON – Women have passed men on the nation’s roads. More women than men have driver’s licenses, a reversal of a longtime gender gap behind the wheel that transportation researchers say is likely to have safety and economic implications.

If current trends continue, the gap only will widen. The share of teens and young adults of both sexes with driver’s licenses is declining, but the decline is greater for young men, according to a study by the University of Michigan’s Transportation Research Institute. The study looked at gender trends in driver’s licenses between 1995 and 2010.

“The changing gender demographics will have major implications on the extent and nature of vehicle demand, energy consumption, and road safety,” predicted Michael Sivak, co-author of the study. Women are more likely than men to purchase smaller, safer and more fuel-efficient cars; to drive less; and to have a lower fatality rate per distance driven, he said.