Frequencies for first 10,000 rows of paytype variable in nhamcsopd2003 dataset :

   expected source of |
              payment |      Freq.     Percent        Cum.
----------------------+-----------------------------------
                blank |         68        0.68        0.68
    private insurance |      3,346       33.46       34.14
             medicare |      1,510       15.10       49.24
             medicaid |      3,519       35.19       84.43
worker's compensation |         84        0.84       85.27
             self-pay |        646        6.46       91.73
            no charge |        249        2.49       94.22
                other |        244        2.44       96.66
              unknown |        334        3.34      100.00
----------------------+-----------------------------------
                Total |     10,000      100.00

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