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

  Unplanned |
  Operation |
627=f_mm_or |
          R |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,715       97.15       97.15
          U |        227        2.27       99.42
          Y |         58        0.58      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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