Frequencies for first 10,000 rows of contsub6 variable in namcs1996 dataset :

 controlled |
  substance |
   code for |
 medication |
         #6 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |          2        0.02        0.02
          3 |         12        0.12        0.14
          4 |         33        0.33        0.47
          5 |          1        0.01        0.48
          6 |        584        5.84        6.32
          7 |          5        0.05        6.37
          . |      9,363       93.63      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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