NEW YORK (AP) -- The number of public high school students who smoke has declined again to its lowest on record, 8.5 percent, city officials said Wednesday.

A survey conducted every two years found that 20,000 high schoolers in the city, out of about 235,000, smoked cigarettes in 2007. Two years earlier, the survey showed 11 percent were smokers, and in 1997 it was 23 percent.

Mayor Michael Bloomberg attributed the decline to a multipronged anti-smoking effort, which includes a tax increase on cigarettes and subway advertisements that depict gruesome stories of tobacco-related illnesses.

"Clearly, teens are getting the message: There's nothing cool about smelling like an ashtray, being hooked on nicotine or dying young," said Bloomberg, a former smoker.

Nationwide, 23 percent of teens smoke, according to 2005 figures, which are the latest available from the Centers for Disease Control and Prevention.

In New York, teen smoking remains highest, at 14.7 percent, in Staten Island, where the rates also are highest among adults.

Bloomberg, a billionaire philanthropist, last year announced he is funding a $125 million worldwide anti-smoking campaign.

The money will go toward programs that help smokers quit and educate children about the risks of starting and toward pushing for smoking bans and higher tobacco taxes in other cities and countries.

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