Frequencies for first 10,000 rows of colon variable in namcs2015 dataset : Colonoscopy | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,884 98.84 98.84 1 | 116 1.16 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 25 Oct 2017