Frequencies for first 10,000 rows of drg2ing4 variable in nhamcsed2005 dataset :

                             ing. #4 |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                      methylene blue |          1        0.01        0.01
                          phenacetin |          1        0.01        0.02
                       potassium ion |          4        0.04        0.06
                          proteinase |          1        0.01        0.07
                          riboflavin |          2        0.02        0.09
                     sodium chloride |          1        0.01        0.10
                            thiamine |          3        0.03        0.13
                    atropine sulfate |          3        0.03        0.16
              hydrocortisone acetate |          5        0.05        0.21
                 hyoscyamine sulfate |         14        0.14        0.35
                dextromethorphan hbr |          1        0.01        0.36
                 diphenhydramine hcl |          1        0.01        0.37
                doxylamine succinate |          1        0.01        0.38
                                   . |      9,962       99.62      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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