Okay, I decided to be a little more proactive. That 20% figure actually only includes adults. The US population is 300 million and 20% of 300 million would yield more than 43.4 million people. The second article makes the number clear.
20 percent of Americans Smoke by Andrea M Kane
"According to the CDC, about 43.4 million Americans (19.8 percent of the population) smoke.
Look around you. If you are in Kentucky, the state with the highest smoking rate, more than one out of every four people (28.3 percent) around you smokes. On the other end of the spectrum is Utah, with just over one person in 10 (11.7 percent) a smoker."
"Poll: 21 Percent of Americans Smoke
July 30, 2007
Just 21 percent of U.S. adults identify themselves as smokers, the lowest rate in 60 years of Gallup polling, the Gallup News Service reported July 25.
Gallup first polled Americans on smoking in 1944, when 44 percent of adults said they smoked. The rate dropped into the 30-38 percent range in the 1970s and 1980s and dipped below 30 percent in 1989.
Statistically, however, the rate reported in the July 2007 poll was unchanged from the 22 percent of Americans who said they smoked in 2004 and the 23 percent who identified themselves as smokers in 1999 and 2006.
Poll respondents also reported smoking fewer cigarettes: a majority of American smokers now consume less than a pack of cigarettes a day; from 1944 to 1999, most cigarette uses smoked more than a pack a day. Less than one in 10 smokers reported smoking more than a pack a day (the balance presumably said they smoked exactly a pack a day).
Gallup found that 25 percent of smokers polled in 2007 said they started smoking before age 16, the lowest rate ever reported.
Twenty-three percent of Americans identified themselves as former smokers; 56 percent said they never smoked.
Most smokers acknowledged that they are addicted to cigarettes (79 percent) and want to quit (81 percent).
Gallup polled more than 1,000 adults ages 18 and over."