Frequencies for first 10,000 rows of stoolcx variable in nhamcsopd2003 dataset : stool | culture | Freq. Percent Cum. ------------+----------------------------------- no | 9,950 99.50 99.50 yes | 50 0.50 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016