Frequencies for first 10,000 rows of rf_cesar variable in linkpe2009psden dataset :

   Previous |
   Cesarean |
 Deliveries |
          R |
(f_rf_cesar |
  rep flag) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      3,422       34.22       34.22
          N |      5,257       52.57       86.79
          U |          1        0.01       86.80
          Y |      1,320       13.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015