Frequencies for first 10,000 rows of monitor variable in natl1998 dataset :

 Electronic |
      fetal |
 monitoring |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      8,391       83.91       83.91
          2 |      1,607       16.07       99.98
          9 |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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