Frequencies for first 10,000 rows of mm_uhyst variable in natl2014 dataset :

  Unplanned |
Hysterectom |
    y Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,814       98.14       98.14
          U |        184        1.84       99.98
          Y |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016