Frequencies for first 10,000 rows of paytype variable in nhamcsopd2006 dataset :

   expected source of |
            payment - |
 hierarchical version |      Freq.     Percent        Cum.
----------------------+-----------------------------------
                Blank |        156        1.56        1.56
    Private insurance |      3,294       32.94       34.50
             Medicare |      1,424       14.24       48.74
             Medicaid |      3,440       34.40       83.14
Worker's compensation |         93        0.93       84.07
             Self-pay |        692        6.92       90.99
            No charge |        310        3.10       94.09
                Other |        327        3.27       97.36
              Unknown |        264        2.64      100.00
----------------------+-----------------------------------
                Total |     10,000      100.00

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