Frequencies for first 10,000 rows of rx5v1c2 variable in nhamcsed2006 dataset :

   for rx5, level 1 of multum |
             drug category #2 |      Freq.     Percent        Cum.
------------------------------+-----------------------------------
              anti-infectives |         10        0.10        0.10
        cardiovascular agents |          8        0.08        0.18
central nervous system agents |         35        0.35        0.53
        coagulation modifiers |         11        0.11        0.64
                     hormones |          1        0.01        0.65
         miscellaneous agents |          6        0.06        0.71
         nutritional products |          2        0.02        0.73
           respiratory agents |         33        0.33        1.06
     psychotherapeutic agents |          3        0.03        1.09
                            . |      9,891       98.91      100.00
------------------------------+-----------------------------------
                        Total |     10,000      100.00

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