Frequencies for first 10,000 rows of role_cod variable in drug2010q1 dataset :

   Code for |
     drug's |
   reported |
    role in |
      event |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          1        0.01        0.01
          C |      5,060       50.60       50.61
          D |          4        0.04       50.65
          I |         87        0.87       51.52
         PS |      2,512       25.12       76.64
         SS |      2,336       23.36      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Dec 2015