Frequencies for first 10,000 rows of contsub6 variable in nhamcsed2003 dataset :

 controlled substance code |
         for medication #6 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         24        0.24        0.24
              schedule iii |         23        0.23        0.47
               schedule iv |         30        0.30        0.77
                schedule v |          2        0.02        0.79
                no control |        439        4.39        5.18
              undetermined |         25        0.25        5.43
                         . |      9,457       94.57      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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