Frequencies for first 10,000 rows of major variable in nhamcsopd2009 dataset :

              major reason for visit |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                               blank |        209        2.09        2.09
new problem (less than 3 mos. onset) |      2,601       26.01       28.10
            chronic problem, routine |      3,516       35.16       63.26
           chronic problem, flare-up |        702        7.02       70.28
                   pre-/post-surgery |        686        6.86       77.14
                     preventive care |      2,286       22.86      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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