Frequencies for first 10,000 rows of mm_rupt variable in natl2013 dataset :

   Ruptured |
     Uterus |
634=f_mm_ru |
     ptur R |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,768       97.68       97.68
          U |        227        2.27       99.95
          Y |          5        0.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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