Frequencies for provtype variable in impact1999 dataset :

   Provider |
       Type |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      3,754       74.04       74.04
          7 |        167        3.29       77.34
          8 |         45        0.89       78.22
         14 |        356        7.02       85.25
         16 |        679       13.39       98.64
         17 |         58        1.14       99.78
         21 |          5        0.10       99.88
         22 |          6        0.12      100.00
------------+-----------------------------------
      Total |      5,070      100.00

by Jean Roth , jroth@nber.org , 17 Mar 2016