Frequencies for first 10,000 rows of contsub3 variable in namcs1996 dataset :

 controlled |
  substance |
   code for |
 medication |
         #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |         25        0.25        0.25
          3 |         87        0.87        1.12
          4 |        183        1.83        2.95
          5 |         21        0.21        3.16
          6 |      3,192       31.92       35.08
          7 |         68        0.68       35.76
          . |      6,424       64.24      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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