Setting a challenging yet realistic smoking prevalence target for Healthy People 2020: learning from the California experience.

OBJECTIVES We sought to outline an optimistic yet achievable goal for future US smoking prevalence rates based on empirical evidence reflecting the success of smoking control efforts in California. METHODS Using a dynamic model and the smoking initiation and cessation rates achieved in California as a guide, we projected US adult smoking prevalence rates through the year 2020. RESULTS If smoking initiation and cessation rates for the nation do not change, population dynamics will result in smoking prevalence rates falling to 19.1% in 2010 and 16.8% in 2020. If the country attains California's initiation and cessation rates by 2010, adult smoking prevalence rates will be 18.5% in 2010 and 14.7% as of 2020. CONCLUSIONS If California's smoking initiation and cessation rates are attained nationwide, the US smoking prevalence rate could be 5.9 percentage points lower than the 2005 rate by the year 2020, and there would be 10.2 million fewer smokers than in 2005. A target of 14% smoking prevalence by 2020 is aggressive yet feasible, given that it takes into account the constraints imposed by population demographics.