Frequencies for first 10,000 rows of prov1500 variable in posclia2008 dataset :

 physicians |
- volunteer |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |     10,000      100.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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