Frequencies for first 10,000 rows of drg2ing4 variable in nhamcsed2004 dataset :

  ingredient code #4 for medication |
                                 #2 |      Freq.     Percent        Cum.
------------------------------------+-----------------------------------
                   chlorpheniramine |          1        0.01        0.01
                 magnesium antacids |          1        0.01        0.02
                      potassium ion |          5        0.05        0.07
                         riboflavin |          1        0.01        0.08
                    sodium chloride |          1        0.01        0.09
                       theophylline |          1        0.01        0.10
                           thiamine |          5        0.05        0.15
                       triprolidine |          2        0.02        0.17
                          vitamin a |          1        0.01        0.18
  zinc topical agents, external use |          1        0.01        0.19
                   atropine sulfate |          2        0.02        0.21
          dextroamphetamine sulfate |          1        0.01        0.22
             hydrocortisone acetate |          1        0.01        0.23
                hyoscyamine sulfate |         13        0.13        0.36
                diphenhydramine hcl |          1        0.01        0.37
                                  . |      9,963       99.63      100.00
------------------------------------+-----------------------------------
                              Total |     10,000      100.00

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