Frequencies for urgeo variable in impact2010 dataset :

      Large |
     Urban, |
Other Urban |
   or Rural |
Designation |
     of the |
  Providers |
 Geographic |
       CBSA |      Freq.     Percent        Cum.
------------+-----------------------------------
     LURBAN |      1,413       39.29       39.29
     OURBAN |      1,163       32.34       71.64
      RURAL |      1,020       28.36      100.00
------------+-----------------------------------
      Total |      3,596      100.00

by Jean Roth , jroth@nber.org , 16 Dec 2016