Frequencies for first 10,000 rows of major variable in nhamcsopd2007 dataset :

              major reason for visit |      Freq.     Percent        Cum.
-------------------------------------+-----------------------------------
                               blank |        156        1.56        1.56
new problem (less than 3 mos. onset) |      2,713       27.13       28.69
            chronic problem, routine |      3,623       36.23       64.92
           chronic problem, flare-up |        696        6.96       71.88
                   pre-/post-surgery |        655        6.55       78.43
                     preventive care |      2,157       21.57      100.00
-------------------------------------+-----------------------------------
                               Total |     10,000      100.00

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