Frequencies for first 10,000 rows of mm_rupt variable in natl2015 dataset :

   Ruptured |
   Uterus Y |
        Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,917       99.17       99.17
          U |         79        0.79       99.96
          Y |          4        0.04      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Oct 2016