Frequencies for first 10,000 rows of contsub5 variable in nhamcsopd2004 dataset :

 controlled substance code |
         for medication #5 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |         40        0.40        0.40
              schedule iii |         10        0.10        0.50
               schedule iv |         48        0.48        0.98
                schedule v |          1        0.01        0.99
                no control |      1,241       12.41       13.40
              undetermined |         29        0.29       13.69
                         . |      8,631       86.31      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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