Fewer people than ever are smoking in the United States, according to figures from the Centers for Disease Control and Prevention, though certain groups are at greater risk than others for indulging in the habit. 

Smoking still kills more people than any other preventable condition in the country, but the CDC says the number of smokers has dropped considerably in the last 10 years, from almost 21 percent of adults in 2005 to about 15 percent of adults last year. However, there were disparities among different groups. For example, men were more likely to smoke than women. The numbers also varied between age groups, with the largest proportion of smokers between 25 and 44 years old, followed by people ages 45 to 64; young adults between 18 and 24 years; and finally people older than 65. Smoking rates also decreased with every rung of education a person reached, from high school diploma to a graduate degree, and with income.

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Race also played a role: the CDC reports that Native Americans and mixed race individuals were the most likely to smoke, followed by blacks, whites, Hispanics and Asians.

Other factors included sexual orientation, with straight adults less likely to smoke than their LGBT counterparts; hometown, with Midwesterners smoking most of all, compared to people in the South, Northeast and West; and disability, with disabled or limited people smoking more.

“We’ve made commendable progress toward reducing smoking, the leading cause of death in this country,” Brian A. King, a deputy director in the office of smoking and health at the CDC, told the New York Times. “But there’s still work to do.”

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