Frequencies for first 10,000 rows of prov2440 variable in pos2006 dataset :

       srv: |
  radiology |
(diagnostic |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,710       87.10       87.10
          0 |         39        0.39       87.49
          1 |        899        8.99       96.48
          2 |        213        2.13       98.61
          3 |        139        1.39      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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