Frequencies for first 10,000 rows of drg4ing5 variable in nhamcsopd1995 dataset :

 ingredient |
code #5 for |
 medication |
         #4 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,991       99.91       99.91
      55755 |          1        0.01       99.92
      56185 |          3        0.03       99.95
      56193 |          2        0.02       99.97
      56265 |          2        0.02       99.99
      56345 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016