CHICAGO - Aggressive efforts to curb smoking led to a sharp drop in the number of smokers in New York City in the past few years, U.S. health experts said on Thursday.

Just 17.5 percent of adults in New York smoked last year, down from 21.6 percent in 2002, after the city brought in higher taxes, smoke-free environments and tough-talking educational campaigns, according to the U.S. Centers for Disease Control and Prevention.

That followed a decade of no progress in the fight to reduce smoking.

New York started its crackdown on smoking in 2002, when it hiked taxes on cigarettes to the highest level in the United States at the time, boosting the retail price by 32 percent per pack. In 2003, it established smoke-free workplaces.

Both measures proved effective and, by 2004, the percentage of adult smokers fell to 18.4 percent.

When smoking rates stalled a bit in 2005, the city ran a year-long television campaign to motivate more smokers to quit.

That resonated with men and Hispanics, with smoking rates falling to 19.9 percent from 22.5 percent among men between 2005 and 2006. Smoking among Hispanics fell to 17.1 percent from 20.2 percent in that period.

"These findings confirm the importance of comprehensive tobacco-control programs and suggest that this intensive, broad-based media campaign has reduced smoking prevalence among certain groups," the CDC said in its weekly report on death and disease.

By 2006, there were 240,000 fewer smokers in New York City than there were in 2002, a change that could prevent at least 80,000 smoking-related deaths, the CDC said.

New York's success comes amid a wave of efforts across the United States to create smoke-free environments such as workplaces, bars and restaurants that curb exposure to secondhand smoke.

So far, 23 states -- plus Puerto Rico and Washington, D.C. -- have enacted smoke-free laws that protect the health of millions of workers and patrons, according to the American Cancer Society.

As a percentage of the U.S. population, 57 percent now live under smoke-free laws at the state or local level, the cancer society said in a report also issued this week.

Since January 1:

-- governors in Tennessee, Maryland, Minnesota and New Mexico have signed comprehensive laws;

-- smoke-free laws in Arizona, Louisiana, New Mexico, Puerto Rico and Washington, D.C. have taken effect;

-- legislatures in Illinois and Oregon have passed smoke-free laws that the governors are expected to sign.

Michigan, Pennsylvania and Wisconsin's state legislatures are currently considering state-wide smoke-free laws.

Tobacco use remains the leading cause of preventable death in the United States, with 435,000 deaths, or 18 percent of all deaths, due to smoking, according to the CDC.