Frequencies for first 10,000 rows of rx8v2c2 variable in nhamcsed2006 dataset :

        for rx8, level 2 of multum drug |
                            category #2 |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
          anti-infectives: sulfanomides |          1        0.01        0.01
coagulation modifiers: antiplatelet age |          2        0.02        0.03
                 hormones: sex hormones |          1        0.01        0.04
    topical agents: vaginal preprations |          1        0.01        0.05
                                      . |      9,995       99.95      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

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