Frequencies for first 10,000 rows of lmpday variable in natlterr1997 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        316        3.16        3.16
          2 |        273        2.73        5.89
          3 |        334        3.34        9.23
          4 |        290        2.90       12.13
          5 |        405        4.05       16.18
          6 |        306        3.06       19.24
          7 |        339        3.39       22.63
          8 |        340        3.40       26.03
          9 |        284        2.84       28.87
         10 |        443        4.43       33.30
         11 |        265        2.65       35.95
         12 |        356        3.56       39.51
         13 |        315        3.15       42.66
         14 |        294        2.94       45.60
         15 |        553        5.53       51.13
         16 |        326        3.26       54.39
         17 |        293        2.93       57.32
         18 |        313        3.13       60.45
         19 |        286        2.86       63.31
         20 |        419        4.19       67.50
         21 |        267        2.67       70.17
         22 |        282        2.82       72.99
         23 |        308        3.08       76.07
         24 |        315        3.15       79.22
         25 |        358        3.58       82.80
         26 |        303        3.03       85.83
         27 |        278        2.78       88.61
         28 |        344        3.44       92.05
         29 |        251        2.51       94.56
         30 |        335        3.35       97.91
         31 |         54        0.54       98.45
         99 |        155        1.55      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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