Frequencies for first 10,000 rows of monitor variable in natl1989 dataset :

 Electronic |
      fetal |
 monitoring |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      7,918       79.18       79.18
          2 |      2,028       20.28       99.46
          9 |         54        0.54      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016