Frequencies for first 10,000 rows of drg3ing4 variable in nhamcsopd1999 dataset : ingredient | code #4 for | medication | #3 | Freq. Percent Cum. ------------+----------------------------------- | 9,995 99.95 99.95 54468 | 2 0.02 99.97 54713 | 1 0.01 99.98 55755 | 1 0.01 99.99 56185 | 1 0.01 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 28 Mar 2016