Frequencies for first 10,000 rows of prov2025 variable in pos1995 dataset :

       self |
   dialysis |
       code |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,943       99.43       99.43
          A |         55        0.55       99.98
          B |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016