Frequencies for first 10,000 rows of contsub5 variable in nhamcsed2007 dataset :

       for rx5, controlled |
     substance status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         61        0.61        0.61
              schedule iii |         53        0.53        1.14
               schedule iv |         30        0.30        1.44
                schedule v |          1        0.01        1.45
                no control |        698        6.98        8.43
              undetermined |         14        0.14        8.57
                         . |      9,143       91.43      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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