Frequencies for first 10,000 rows of contsub2 variable in namcs2002 dataset :

Controlled status code for |
             medication #2 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         54        0.54        0.54
              Schedule III |         81        0.81        1.35
               Schedule IV |        126        1.26        2.61
                Schedule V |         22        0.22        2.83
                No control |      3,126       31.26       34.09
              Undetermined |        116        1.16       35.25
                         . |      6,475       64.75      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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