Frequencies for first 10,000 rows of contsub6 variable in namcs2008 dataset :

    controlled status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         26        0.26        0.26
              schedule iii |         27        0.27        0.53
               schedule iv |         63        0.63        1.16
                schedule v |          5        0.05        1.21
                no control |      1,365       13.65       14.86
              undetermined |         13        0.13       14.99
        multiple schedules |          3        0.03       15.02
                         . |      8,498       84.98      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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