Frequencies for first 10,000 rows of exercise variable in nhamcsopd2009 dataset : exercise | Freq. Percent Cum. ------------+----------------------------------- no | 9,203 92.03 92.03 yes | 797 7.97 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016