Frequencies for first 10,000 rows of contsub5 variable in nhamcsopd2003 dataset :

 controlled substance code |
         for medication #5 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         41        0.41        0.41
              schedule iii |         22        0.22        0.63
               schedule iv |         44        0.44        1.07
                schedule v |          6        0.06        1.13
                no control |      1,123       11.23       12.36
              undetermined |         27        0.27       12.63
                         . |      8,737       87.37      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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