Frequencies for first 10,000 rows of mm_uhyst variable in natl2017 dataset :

  Unplanned |
Hysterectom |
    y Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,935       99.35       99.35
          U |         57        0.57       99.92
          Y |          8        0.08      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 19 Sep 2018