Frequencies for first 10,000 rows of contsub5 variable in namcs2008 dataset :

    controlled status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         30        0.30        0.30
              schedule iii |         15        0.15        0.45
               schedule iv |         82        0.82        1.27
                schedule v |          6        0.06        1.33
                no control |      1,909       19.09       20.42
              undetermined |         29        0.29       20.71
        multiple schedules |          4        0.04       20.75
                         . |      7,925       79.25      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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