Frequencies for first 10,000 rows of contsub3 variable in nhamcsed2002 dataset :

 controlled |
  substance |
   code for |
    drug #3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |        122        1.22        1.22
          3 |         71        0.71        1.93
          4 |         82        0.82        2.75
          5 |          6        0.06        2.81
          6 |      1,846       18.46       21.27
          7 |         84        0.84       22.11
          . |      7,789       77.89      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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