Frequencies for first 10,000 rows of dlmp_yy variable in natlterr2007 dataset :

Last Normal |
   Menses - |
   Year U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
       2006 |      7,133       71.33       71.33
       2007 |      1,072       10.72       82.05
       9999 |      1,795       17.95      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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