Frequencies for first 10,000 rows of ume_forcep variable in natl2014 dataset :

  Forceps 1 |
        Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        209        2.09        2.09
          2 |      9,784       97.84       99.93
          9 |          7        0.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016