Frequencies for first 10,000 rows of drg3ing5 variable in nhamcsopd1998 dataset : ingredient | code #5 for | medication | #3 | Freq. Percent Cum. ------------+----------------------------------- | 9,992 99.92 99.92 55755 | 1 0.01 99.93 56185 | 3 0.03 99.96 56192 | 1 0.01 99.97 56195 | 3 0.03 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016