Frequencies for first 10,000 rows of contsub18 variable in namcs2015 dataset :

 Controlled |
  substance |
   code for |
 medication |
        #18 |      Freq.     Percent        Cum.
------------+-----------------------------------
          4 |          2        0.02        0.02
          5 |          2        0.02        0.04
          6 |         88        0.88        0.92
          7 |          2        0.02        0.94
          8 |          1        0.01        0.95
          . |      9,905       99.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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