Frequencies for first 10,000 rows of contsub1 variable in namcs1999 dataset :

 controlled |
  substance |
   code for |
 medication |
         #1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |        121        1.21        1.21
          3 |        108        1.08        2.29
          4 |        208        2.08        4.37
          5 |         28        0.28        4.65
          6 |      5,680       56.80       61.45
          7 |        213        2.13       63.58
          . |      3,642       36.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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