Frequencies for first 10,000 rows of lmpyr variable in natl1986 dataset :

  Year Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          - |        319        3.19        3.19
          5 |      9,610       96.10       99.29
          6 |         71        0.71      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016