Frequencies for first 10,000 rows of contsub1 variable in namcs1995 dataset :

 controlled |
  substance |
   code for |
 medication |
         #1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |         54        0.54        0.54
          3 |        107        1.07        1.61
          4 |        197        1.97        3.58
          5 |         31        0.31        3.89
          6 |      6,539       65.39       69.28
          7 |        360        3.60       72.88
          . |      2,712       27.12      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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