In 2018, 60.6% of U.S. adults aged 50–75 years without a personal history of colorectal cancer had a colonoscopy in the past 10 years.
Of these, 81.2% had their most recent colonoscopy as part of routine screening, 10.6% had their most recent colonoscopy because of a problem, 5.2% as a follow-up to an earlier test or screening exam, and 2.8% for some other reason.
Source: National Health Interview Survey, 2018. https://www.cdc.gov/nchs/nhis.htm.