Frequencies for first 10,000 rows of contsub3 variable in nhamcsopd2003 dataset :

 controlled substance code |
         for medication #3 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         87        0.87        0.87
              schedule iii |         24        0.24        1.11
               schedule iv |        107        1.07        2.18
                schedule v |          3        0.03        2.21
                no control |      2,240       22.40       24.61
              undetermined |         59        0.59       25.20
                         . |      7,480       74.80      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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