Frequencies for first 10,000 rows of lmpday variable in natlterr2001 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        296        2.96        2.96
          2 |        292        2.92        5.88
          3 |        327        3.27        9.15
          4 |        299        2.99       12.14
          5 |        458        4.58       16.72
          6 |        316        3.16       19.88
          7 |        314        3.14       23.02
          8 |        308        3.08       26.10
          9 |        281        2.81       28.91
         10 |        459        4.59       33.50
         11 |        253        2.53       36.03
         12 |        343        3.43       39.46
         13 |        264        2.64       42.10
         14 |        310        3.10       45.20
         15 |        532        5.32       50.52
         16 |        319        3.19       53.71
         17 |        339        3.39       57.10
         18 |        322        3.22       60.32
         19 |        259        2.59       62.91
         20 |        468        4.68       67.59
         21 |        226        2.26       69.85
         22 |        273        2.73       72.58
         23 |        290        2.90       75.48
         24 |        273        2.73       78.21
         25 |        362        3.62       81.83
         26 |        329        3.29       85.12
         27 |        274        2.74       87.86
         28 |        296        2.96       90.82
         29 |        238        2.38       93.20
         30 |        298        2.98       96.18
         31 |         79        0.79       96.97
         99 |        303        3.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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