Frequencies for first 10,000 rows of drug2cl3 variable in nhamcsed2004 dataset :

        drug class #3 for medication #2 |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
               calcium channel blockers |          1        0.01        0.01
                         ace inhibitors |          2        0.02        0.03
repl/regs of electrolytes/water balance |          3        0.03        0.06
                          immune serums |          1        0.01        0.07
                     topical analgesics |          1        0.01        0.08
                        anticonvulsants |         49        0.49        0.57
                cycloplegics/mydriatics |          4        0.04        0.61
ocular anti-infective/anti-inflammatory |          8        0.08        0.69
              miscellaneous ophthalmics |          1        0.01        0.70
                   otic, topical (misc) |          1        0.01        0.71
                                  nsaid |          1        0.01        0.72
                           antipyretics |         82        0.82        1.54
         antiasthmatics/bronchodilators |          8        0.08        1.62
                         antihistamines |        370        3.70        5.32
                          cold remedies |          9        0.09        5.41
                    pharmaceutical aids |          2        0.02        5.43
                          surgical aids |         58        0.58        6.01
                                      . |      9,399       93.99      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

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