Frequencies for first 10,000 rows of me_trial variable in natl2016 dataset :

   Trial of |
      Labor |
  Attempted |
        (if |
cesarean) Y |
        Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      1,381       13.81       13.81
          U |         55        0.55       14.36
          X |      7,727       77.27       91.63
          Y |        837        8.37      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 4 Oct 2017