Frequencies for first 10,000 rows of urf_phyper variable in natl2012 dataset :

  Pregnancy |
 Associated |
Hypertensio |
      n RFP |
689=f_urf_p |
  hyper U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        505        5.05        5.05
          2 |      7,055       70.55       75.60
          9 |      2,440       24.40      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 5 May 2016