Frequencies for first 10,000 rows of drg4ing5 variable in nhamcsed2000 dataset :

 ingredient |
code #5 for |
    drug #4 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,995       99.95       99.95
      55150 |          1        0.01       99.96
      55348 |          2        0.02       99.98
      56195 |          1        0.01       99.99
      56345 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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