Frequencies for first 10,000 rows of asthmaed variable in nhamcsopd2001 dataset : asthma | education | Freq. Percent Cum. ------------+----------------------------------- 0 | 9,882 98.82 98.82 1 | 118 1.18 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016