Frequencies for first 10,000 rows of contsub3 variable in nhamcsed2007 dataset :

       for rx3, controlled |
     substance status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |        267        2.67        2.67
              schedule iii |        201        2.01        4.68
               schedule iv |        102        1.02        5.70
                schedule v |         11        0.11        5.81
                no control |      2,392       23.92       29.73
              undetermined |         48        0.48       30.21
                         . |      6,979       69.79      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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