Frequencies for first 10,000 rows of contsub7 variable in namcs2007 dataset :

    controlled status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         12        0.12        0.12
              schedule iii |         13        0.13        0.25
               schedule iv |         34        0.34        0.59
                schedule v |          9        0.09        0.68
                no control |        851        8.51        9.19
              undetermined |         11        0.11        9.30
                         . |      9,070       90.70      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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