Frequencies for first 10,000 rows of uop_monit variable in natlterr2003 dataset :

 Electronic |
      Fetal |
 Monitoring |
          U |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      8,396       83.96       83.96
          2 |      1,581       15.81       99.77
          8 |         23        0.23      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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