Frequencies for first 10,000 rows of role_cod variable in drug2010q4 dataset :

   Code for |
     drug's |
   reported |
    role in |
      event |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          1        0.01        0.01
          C |      5,492       54.92       54.93
          D |          2        0.02       54.95
          I |         54        0.54       55.49
         PS |      2,586       25.86       81.35
         SS |      1,865       18.65      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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