Frequencies for first 10,000 rows of contsub7 variable in nhamcsopd2006 dataset :

       for rx7, controlled |
     substance status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               Schedule II |         10        0.10        0.10
              Schedule III |          8        0.08        0.18
               Schedule IV |         34        0.34        0.52
                Schedule V |          2        0.02        0.54
                No control |        714        7.14        7.68
              Undetermined |          9        0.09        7.77
                         . |      9,223       92.23      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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