Frequencies for first 10,000 rows of asthmaed variable in nhamcsopd2008 dataset : asthma | education | Freq. Percent Cum. ------------+----------------------------------- no | 9,852 98.52 98.52 yes | 148 1.48 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016