Frequencies for first 10,000 rows of asthmaed variable in nhamcsopd2011 dataset : Asthma | education | Freq. Percent Cum. ------------+----------------------------------- No | 9,862 98.62 98.62 Yes | 138 1.38 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016