Frequencies for first 10,000 rows of prov2440 variable in pos1994 dataset :

       srv: |
  radiology |
(diagnostic |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,940       89.40       89.40
          0 |         25        0.25       89.65
          1 |        793        7.93       97.58
          2 |        167        1.67       99.25
          3 |         75        0.75      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017