Frequencies for first 10,000 rows of ekg variable in nhamcsed2008 dataset : ekg/ecg | (electrocar | diogram) | Freq. Percent Cum. ------------+----------------------------------- no | 8,051 80.51 80.51 yes | 1,949 19.49 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016