Frequencies for first 10,000 rows of ume_repec variable in natl2008 dataset :

     Repeat |
  C-Section |
        RFP |
733=f_u_rep |
       ec U |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,359       13.59       13.59
          2 |      8,586       85.86       99.45
          9 |         55        0.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 May 2016