Frequencies for pmcarr_i1 variable in parkwork dataset :

       MCID |
    Issuing |
  Authority |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        900       84.59       84.59
          2 |          1        0.09       84.68
          6 |          8        0.75       85.43
         15 |          1        0.09       85.53
         18 |          1        0.09       85.62
         27 |          1        0.09       85.71
         57 |         87        8.18       93.89
         58 |          1        0.09       93.98
         77 |         20        1.88       95.86
         88 |         22        2.07       97.93
         99 |         22        2.07      100.00
------------+-----------------------------------
      Total |      1,064      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016