Frequencies for first 10,000 rows of monitor variable in natl1992 dataset :

 Electronic |
      fetal |
 monitoring |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      8,791       87.91       87.91
          2 |      1,198       11.98       99.89
          9 |         11        0.11      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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