Frequencies for first 10,000 rows of contsub5 variable in nhamcsed2008 dataset :

       for rx5, controlled |
     substance status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         68        0.68        0.68
              schedule iii |         55        0.55        1.23
               schedule iv |         31        0.31        1.54
                schedule v |          2        0.02        1.56
                no control |        689        6.89        8.45
              undetermined |         17        0.17        8.62
        multiple schedules |          4        0.04        8.66
                         . |      9,134       91.34      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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