Frequencies for first 10,000 rows of contsub8 variable in nhamcsopd2009 dataset :

       for rx8, controlled |
     substance status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         20        0.20        0.20
              schedule iii |         22        0.22        0.42
               schedule iv |         41        0.41        0.83
                schedule v |          1        0.01        0.84
                no control |        860        8.60        9.44
              undetermined |          9        0.09        9.53
        multiple schedules |          3        0.03        9.56
                         . |      9,044       90.44      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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