Nearly 87 percent of all lung cancers are smoking-related. If caught early, chances of survival increase greatly, which is why health experts encourage current and former smokers to undergo screening.
The good news is that the percentage of U.S. adults who smoke has fallen significantly over the past decades and has continued to decline over the last 10 years. Back in the 1950s and '60s, two in every five U.S. adults smoked. In 2005, that rate had fallen to one in every five, or 20 percent. In 2014, the rate was even lower, around 16.8 percent of the adult population. Public health officials have set a goal of bringing the rate down to 12 percent by 2020.