Frequencies for first 10,000 rows of prov2445 variable in pos2004 dataset :

       srv: |
  radiology |
(therapeuti |
         c) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,766       87.66       87.66
          0 |        786        7.86       95.52
          1 |        250        2.50       98.02
          2 |        156        1.56       99.58
          3 |         42        0.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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