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

   Perineal |
 Laceration |
      Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,818       98.18       98.18
          U |         39        0.39       98.57
          Y |        143        1.43      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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