Frequencies for first 10,000 rows of prov2440 variable in pos2007 dataset :

       srv: |
  radiology |
(diagnostic |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,682       86.82       86.82
          0 |         56        0.56       87.38
          1 |        898        8.98       96.36
          2 |        216        2.16       98.52
          3 |        148        1.48      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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