(A) Trends in colonoscopy use per 1,000 person-years. (B) Trends in age-standardized (2000 United States census population) colorectal cancer incidence per 100,000 person-years, crude and adjusted for colonoscopy use. (C) Trends in diagnostic and screening colonoscopy use per 1,000 person-years. (D) Trends in age-standardized (2000 United States census population) early- and advanced-stage colorectal cancer incidence per 100,000 person-years. Regression lines represent annual average percent change.