Frequencies for first 10,000 rows of contsub22 variable in namcs2015 dataset :

 Controlled |
  substance |
   code for |
 medication |
        #22 |      Freq.     Percent        Cum.
------------+-----------------------------------
          3 |          1        0.01        0.01
          4 |          3        0.03        0.04
          6 |         29        0.29        0.33
          7 |          1        0.01        0.34
          . |      9,966       99.66      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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