Frequencies for first 10,000 rows of uld_ruptr variable in natlterr2006 dataset :

  Premature |
 Rupture of |
   Membrane |
        RFP |
713=f_uld_r |
   upture U |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         13        0.13        0.13
          2 |      4,721       47.21       47.34
          9 |      1,541       15.41       62.75
          . |      3,725       37.25      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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