Frequencies for first 10,000 rows of contsub1 variable in nhamcsed2004 dataset :

 controlled substance code |
         for medication #1 |      Freq.     Percent        Cum.
---------------------------+-----------------------------------
               schedule ii |        603        6.03        6.03
              schedule iii |        584        5.84       11.87
               schedule iv |        257        2.57       14.44
                schedule v |         14        0.14       14.58
                no control |      6,070       60.70       75.28
              undetermined |        126        1.26       76.54
                         . |      2,346       23.46      100.00
---------------------------+-----------------------------------
                     Total |     10,000      100.00

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