Frequencies for first 10,000 rows of contsub1 variable in namcs2012 dataset :

    Controlled status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |        193        1.93        1.93
              Schedule III |        189        1.89        3.82
               Schedule IV |        224        2.24        6.06
                Schedule V |         29        0.29        6.35
                No control |      5,963       59.63       65.98
              Undetermined |        225        2.25       68.23
        Multiple schedules |         16        0.16       68.39
                         . |      3,161       31.61      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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