Frequencies for first 10,000 rows of drug2cl3 variable in nhamcsopd2004 dataset :

        drug class #3 for medication #2 |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
               calcium channel blockers |          2        0.02        0.02
                         ace inhibitors |          1        0.01        0.03
repl/regs of electrolytes/water balance |          1        0.01        0.04
                       topical steroids |          1        0.01        0.05
                     topical analgesics |          2        0.02        0.07
                        anticonvulsants |         18        0.18        0.25
                cycloplegics/mydriatics |          3        0.03        0.28
ocular anti-infective/anti-inflammatory |          2        0.02        0.30
                   otic, topical (misc) |          1        0.01        0.31
                           antipyretics |         69        0.69        1.00
                          antimalarials |          1        0.01        1.01
         antiasthmatics/bronchodilators |          1        0.01        1.02
                         antihistamines |         18        0.18        1.20
                          cold remedies |          2        0.02        1.22
                    pharmaceutical aids |          3        0.03        1.25
                          surgical aids |         16        0.16        1.41
                                      . |      9,859       98.59      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

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