Frequencies for first 10,000 rows of sigcolon variable in nhamcsopd2008 dataset : sigmoidosco | py/colonosc | opy | Freq. Percent Cum. ------------+----------------------------------- no | 9,882 98.82 98.82 yes | 118 1.18 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016