Frequencies for first 10,000 rows of rx1v1c1 variable in nhamcsed2006 dataset :

   for rx1, level 1 of multum |
             drug category #1 |      Freq.     Percent        Cum.
------------------------------+-----------------------------------
              anti-infectives |      1,350       13.50       13.50
              antineoplastics |          5        0.05       13.55
        cardiovascular agents |        340        3.40       16.95
central nervous system agents |      3,894       38.94       55.89
        coagulation modifiers |         48        0.48       56.37
      gastrointestinal agents |        337        3.37       59.74
                     hormones |        203        2.03       61.77
         miscellaneous agents |        142        1.42       63.19
         nutritional products |        367        3.67       66.86
           respiratory agents |        468        4.68       71.54
               topical agents |        283        2.83       74.37
     psychotherapeutic agents |         38        0.38       74.75
         immunological agents |        189        1.89       76.64
            radiologic agents |          3        0.03       76.67
             metabolic agents |         41        0.41       77.08
           pharmaceutical aid |          1        0.01       77.09
                            . |      2,291       22.91      100.00
------------------------------+-----------------------------------
                        Total |     10,000      100.00

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