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

  Induction |
   of labor |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,369       13.69       13.69
          2 |      8,602       86.02       99.71
          9 |         29        0.29      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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