Here is some relief, at least to this nervous momma: The number of 16-year-olds with driver's licenses have dropped from nearly half to less than a third in the last 10 years, according to a story in The New York Times. The reasons for the decline vary from more strict state driving requirements to higher insurance rates and a shift from high school drivers ed to private classes, which are more expensive.

To that mix, experts also add parents who are willing to chauffeur their children to activities, and pastimes like surfing the Web that keep them indoors and glued to computers.

Jaclyn Frederick, 17, of suburban Detroit, is a year past the age when she could get a Michigan license. She said she planned to apply for one eventually, but sees no rush.

“Oh, I guess I just haven’t done it yet, you know?” said Jaclyn, a senior at Ferndale High School, in Ferndale, Mich.

“I get rides and stuff, so I’m not worried about it. I’ll get around to it, maybe this summer sometime.”

Until she does, she has company. The national rate of licensed 16-year-olds dropped to 29.8 percent in 2006 from 43.8 percent in 1998, according to the Federal Highway Administration.

The falling rate of teenage drivers is perplexing to Michael T. Marsden, an expert on car culture and dean of St. Norbert College in De Pere, Wis.

“It’s a big change in a major American ritual of driving as early as possible,” Mr. Marsden said.