Frequencies for first 10,000 rows of typepay variable in nhamcsopd1996 dataset :

     expected type of payment for visit |      Freq.     Percent        Cum.
----------------------------------------+-----------------------------------
No answer, both parts A and B were blan |        321        3.21        3.21
              Preferred Provider Option |        372        3.72        6.93
               Insured, fee-for-service |      4,066       40.66       47.59
                      HMO/Other prepaid |      2,124       21.24       68.83
                               Self-pay |      1,241       12.41       81.24
                              No charge |        348        3.48       84.72
                                  Other |        327        3.27       87.99
Type of payment unspec, but insurance c |      1,201       12.01      100.00
----------------------------------------+-----------------------------------
                                  Total |     10,000      100.00

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