WASHINGTON (AP) — For all the criticism and new legal bans, texting by drivers just keeps increasing, especially among younger motorists.

About half of American drivers between 21 and 24 say they've thumbed messages or emailed from the driver's seat. And what's more, many drivers don't think it's dangerous when they do it — only when others do.

A national survey, the first government study of its kind on distracted driving, and other data released Thursday by the National Highway Traffic Safety Administration underscore the difficulty authorities face in discouraging texting and cellphone talking while driving.

At any given moment last year on America's streets and highways, nearly one in every 100 car drivers was texting, emailing, surfing the Web or otherwise using a hand-held electronic device, the safety administration said. And those activities spiked 50 percent over the previous year, even as states rush to ban the practices.

Last month, Pennsylvania became the 35th state to forbid texting while driving.

In 2010 there were an estimated 3,092 deaths in crashes affected by a wide range of driver distractions, from eating meals to thumbing email, the safety administration said. That number was derived using a new methodology aimed at getting a more precise picture of distracted driving deaths and can't be compared to tallies from previous years, officials said.

The agency takes an annual snapshot of drivers' behavior behind the wheel by staking out intersections to count people using cellphones and other devices, as well as other distracting behavior.

While electronic gadgets are in ever greater use by drivers, motorists are deeply conflicted about it, a NHTSA survey of over 6,000 drivers found.

Most said they would answer a cellphone call while driving and continue to drive after answering. And nearly two of 10 acknowledged sending texts or emails from behind the wheel. That spiked up to half of drivers 21 to 24 years old.

More than half of drivers said making a cellphone call made no difference to their driving performance, and a quarter said texting or emailing made no difference. But 90 percent said that when they are passengers they feel very unsafe if the driver is texting or emailing.

Indeed, big majorities of drivers surveyed support bans on hand-held cellphone use and texting while driving — 71 percent and 94 percent, respectively. And most said they want people who violate the bans to be punished with fines of $100 or more. Almost a quarter supported fines in the $200 to $499 range.

"Everyone thinks he or she is an above average driver — it's all the nuts out there who need educating," said Russ Rader, a spokesman for the Insurance Institute for Highway Safety.

About twice as many drivers reported answering incoming calls as making calls while driving, 71 percent to 41 percent. And more drivers reported reading than sending texts or emails.

There were very few situations in which drivers said they would never talk on the phone or send texts. Bad weather was the most frequent reason cited. Few drivers said they would never place a call or send a message if they'd seen a police officer, had a child on board or were driving at nighttime or in a marked school zone.

The survey results "help us understand why some people continue to make bad decisions about driving distracted," NHTSA Administrator David Strickland said. "But what's clear from all of the information we have is that driver distraction continues to be a major problem."

The increase in texting while driving came even though many states have banned the practice, and that's alarming, said Jonathan Adkins, a spokesman for the Governors Highway Safety Association.

"It is clear that educational messages alone aren't going to change their behavior," Adkins said. "Rather, good laws with strong enforcement are what is needed. Many drivers won't stop texting until they fear getting a ticket."

The safety administration reported earlier this year that pilot projects in Syracuse, N.Y., and Hartford, Conn., produced significant reductions in distracted driving by combining stepped-up ticketing with high-profile public education campaigns.

Before and after each enforcement wave, NHTSA researchers observed cellphone use by drivers and conducted surveys at drivers' license offices in the two cities. They found that in Syracuse, hand-held cellphone use and texting declined by a third. In Hartford, there was a 57 percent drop in hand-held phone use, and texting behind the wheel dropped by nearly three-quarters.

However, that was with blanket enforcement by police.

"The key measure of all this is, do these restrictions reduce crashes? So far, there is no evidence that crashes are reduced when cellphone and texting restrictions are implemented," Rader said.

Overall, 32,885 people died in traffic crashes in the United States in 2010, a nearly 3 percent drop and the lowest number since 1949. Traffic deaths have been declining for several years. Safety researchers generally attribute the lower deaths to a decline in driving because of the poor economy combined with better designed and equipped cars and stronger safety laws.

Bucking the trend, there were 4,502 motorcycle deaths in 2010, a 0.7 percent increase. That may mean the sudden 16 percent decline in motorcycle deaths in 2009 is beginning to reverse. Overall, motorcycle deaths have doubled since 1995.