Frequencies for first 10,000 rows of uop_induc variable in natl2009 dataset :

  Induction |
   of labor |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,682       26.82       26.82
          2 |      7,310       73.10       99.92
          9 |          8        0.08      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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