The federal Centers for Disease Control and Prevention says lung cancer incidence rates declined nearly 3 per cent per year among men and about 1 per cent per year among women from 2005 to 2009.
The biggest decline was in the 35-to-44-year-old age group, where rates fell about 6 per cent per year for both sexes combined.
Officials credited tobacco control efforts. Smoking rates have been steadily declining for years, and the most recent figures suggest that about 18 per cent of adults smoke.
Lung cancer remains the top cancer killer in the U.S. and worldwide. This week marks the 50th anniversary of the first Surgeon General's report tying cigarette smoking to lung cancer.