Frequencies for first 10,000 rows of nebuther variable in nhamcsed2010 dataset : Nebulizer | therapy | Freq. Percent Cum. ------------+----------------------------------- no | 9,710 97.10 97.10 yes | 290 2.90 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016