Frequencies for first 10,000 rows of contsub5 variable in namcs1998 dataset :

 controlled |
  substance |
   code for |
 medication |
         #5 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |          3        0.03        0.03
          3 |          6        0.06        0.09
          4 |         27        0.27        0.36
          5 |          2        0.02        0.38
          6 |        530        5.30        5.68
          7 |         10        0.10        5.78
          . |      9,422       94.22      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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