Frequencies for first 10,000 rows of prov2440 variable in pos1993 dataset :

       srv: |
  radiology |
(diagnostic |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,856       88.56       88.56
          0 |         26        0.26       88.82
          1 |        865        8.65       97.47
          2 |        170        1.70       99.17
          3 |         83        0.83      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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