Frequencies for first 10,000 rows of monitor variable in natl1996 dataset :

 Electronic |
      fetal |
 monitoring |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      8,180       81.80       81.80
          2 |      1,791       17.91       99.71
          9 |         29        0.29      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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