Frequencies for first 10,000 rows of contsub1 variable in namcs2006 dataset :

       for rx1, controlled |
     substance status code |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |        225        2.25        2.25
              schedule iii |        156        1.56        3.81
               schedule iv |        198        1.98        5.79
                schedule v |         47        0.47        6.26
                no control |      6,699       66.99       73.25
              undetermined |        239        2.39       75.64
                         . |      2,436       24.36      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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