Frequencies for first 10,000 rows of contsub15 variable in namcs2015 dataset :

 Controlled |
  substance |
   code for |
 medication |
        #15 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |          2        0.02        0.02
          3 |          7        0.07        0.09
          4 |          7        0.07        0.16
          6 |        216        2.16        2.32
          7 |          6        0.06        2.38
          . |      9,762       97.62      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 25 Oct 2017