Frequencies for first 10,000 rows of prov2440 variable in pos1997 dataset :

       srv: |
  radiology |
(diagnostic |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,792       87.92       87.92
          0 |         23        0.23       88.15
          1 |        883        8.83       96.98
          2 |        200        2.00       98.98
          3 |        102        1.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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