Frequencies for first 10,000 rows of drg2ing5 variable in nhamcsed1999 dataset : ingredient | code #5 for | drug #2 | Freq. Percent Cum. ------------+----------------------------------- | 9,986 99.86 99.86 55348 | 8 0.08 99.94 55755 | 1 0.01 99.95 56185 | 4 0.04 99.99 56265 | 1 0.01 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016