Frequencies for first 10,000 rows of prov2440 variable in pos1992 dataset :

       srv: |
  radiology |
(diagnostic |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,851       88.51       88.51
          0 |         28        0.28       88.79
          1 |        868        8.68       97.47
          2 |        174        1.74       99.21
          3 |         79        0.79      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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