Frequencies for first 10,000 rows of lmpyr variable in natl1995 dataset :

  Year Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
       1994 |      9,658       96.58       96.58
       1995 |          1        0.01       96.59
       9999 |        341        3.41      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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