Frequencies for first 10,000 rows of drg5ing3 variable in nhamcsopd1997 dataset : ingredient | code #3 for | medication | #5 | Freq. Percent Cum. ------------+----------------------------------- | 9,992 99.92 99.92 54755 | 1 0.01 99.93 55080 | 1 0.01 99.94 55105 | 2 0.02 99.96 55240 | 1 0.01 99.97 55770 | 2 0.02 99.99 56340 | 1 0.01 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016