Frequencies for first 10,000 rows of lmpyr variable in natl2002 dataset :

  Year Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
       2001 |      7,298       72.98       72.98
       2002 |      2,291       22.91       95.89
       9999 |        411        4.11      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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