Frequencies for first 10,000 rows of contsub1 variable in namcs1993 dataset :

 controlled |
  substance |
   code for |
 medication |
         #1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |         55        0.55        0.55
          3 |         87        0.87        1.42
          4 |        154        1.54        2.96
          5 |         45        0.45        3.41
          6 |      6,087       60.87       64.28
          7 |        398        3.98       68.26
          . |      3,174       31.74      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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