Frequencies for first 10,000 rows of contsub2 variable in namcs1997 dataset :

 controlled |
  substance |
   code for |
 medication |
         #2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |         42        0.42        0.42
          3 |        107        1.07        1.49
          4 |        372        3.72        5.21
          5 |         43        0.43        5.64
          6 |      5,109       51.09       56.73
          7 |        117        1.17       57.90
          . |      4,210       42.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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