Smoking rates have declined significantly since the U.S. Surgeon General’s report first showed Americans the negative effects of smoking 50 years ago. But a new analysis reveals that smoking cessation is being driven mainly by a small number of populations across the U.S.

Researchers at the the University of Washington looked at how smoking rates broke down by county, and found that Southern counties, such as those in states like Kentucky, Tennessee, and West Virginia, have the highest smoking rates, whereas those in Utah and Western sates have some of the lowest.

“We know what works in tobacco control. It’s taxation. It’s smoking bans. It’s advertising bans, among other measures,” said IHME Director Dr. Christopher Murray in a statement. “We now need to understand what is happening on the ground in these counties that is leading to such great success in parts of New York, Iowa, and Texas, and near total stagnation in parts of Montana, Oklahoma, and Mississippi.”

Virginia saw the widest gap between highest and lowest smoking rates for men between counties: Falls Church City, where 9.9% of men are smokers, and Sussex County, where 33.5% of men are smokers. For women smokers, Alaska had the biggest disparity, with 15.4% women smokers in Haines Borough and a whopping 40.8% in Northwest Arctic Borough.

Smoking rates are tied closely to life expectancy, which can result in one county having a decades longer lifespan than another nearby one. The numbers also highlight the effectiveness local jurisdictions can have on smoking habits.

The study, which looked at smoking rates from 1996 to 2012, showed that much of the drop has occurred in the last 10 years. Nationally, smoking rates for men have dropped from 27.3% to 22.2%, and for women from 22.2% to 17.9%.

Counties with the fastest declines and the biggest annual increases in total cigarette smoking prevalence between 1996 and 2012 for men:

Decreases:

Falls Church City, VA -4.5%

Arlington County, VA -3.2%

San Francisco County, CA -3.1%

Loudoun County, VA -2.9%

New York County, NY -2.8%

Orange County, CA -2.8%

Dallas County, IA -2.8%

Rockingham County, NH -2.8%

San Mateo County, CA -2.8%

Utah County, UT -2.8%

Increases:

Issaquena County, MS 1.1%

Meagher County, MT 0.9%

Bent County, CO 0.8%

Hardy County, WV 0.7%

East Carroll Parish, LA 0.7%

Wheeler County, GA 0.6%

Benson County, ND 0.5%

Claiborne County, MS 0.5%

Lee County, AR 0.5%

Lincoln County, AR 0.4%

Counties with the fastest declines and the biggest annual increases in total cigarette smoking prevalence between 1996 and 2012 for women:

Decreases:

Maverick County, TX -4.1%

Hidalgo County, TX -3.7%

San Luis Obispo County, CA -3.7%

Falls Church City, VA -3.7%

Webb County, TX -3.6%

Santa Barbara County, CA -3.5%

San Francisco County, CA -3.5%

San Mateo County, CA -3.4%

Wasatch County, UT -3.4%

Chittenden County, VT -3.3%

Increases:

McMullen County, TX 1.7%

Mineral County, WV 1.6%

Muskogee County, OK 1.4%

Allen Parish, LA 1.4%

Bristol City, VA 1.4%

Benson County, ND 1.3%

Grant County, WV 1.2%

Hampshire County, WV 1.2%

Adair County, OK 1.2%

Sullivan County, TN 1.2%

The study was published in the journal Population Health Metrics.

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