Frequencies for first 10,000 rows of refmdcar variable in namcs2003 dataset :

 difficulty |
  referring |
   medicare |
    pat for |
    consult |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        564        5.64        5.64
          1 |         93        0.93        6.57
          2 |        825        8.25       14.82
          3 |      1,170       11.70       26.52
          4 |      6,085       60.85       87.37
          5 |      1,263       12.63      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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