Frequencies for first 10,000 rows of drg4ing4 variable in nhamcsopd2003 dataset : ingredient code #4 for medication | #4 | Freq. Percent Cum. ------------------------------------+----------------------------------- sodium chloride | 3 0.03 0.03 thiamine | 7 0.07 0.10 dextroamphetamine sulfate | 1 0.01 0.11 . | 9,989 99.89 100.00 ------------------------------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016