Frequencies for first 10,000 rows of lmpday variable in natlterr1999 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        311        3.11        3.11
          2 |        250        2.50        5.61
          3 |        332        3.32        8.93
          4 |        315        3.15       12.08
          5 |        416        4.16       16.24
          6 |        298        2.98       19.22
          7 |        338        3.38       22.60
          8 |        298        2.98       25.58
          9 |        285        2.85       28.43
         10 |        474        4.74       33.17
         11 |        297        2.97       36.14
         12 |        334        3.34       39.48
         13 |        304        3.04       42.52
         14 |        298        2.98       45.50
         15 |        585        5.85       51.35
         16 |        284        2.84       54.19
         17 |        299        2.99       57.18
         18 |        301        3.01       60.19
         19 |        271        2.71       62.90
         20 |        444        4.44       67.34
         21 |        239        2.39       69.73
         22 |        287        2.87       72.60
         23 |        290        2.90       75.50
         24 |        285        2.85       78.35
         25 |        366        3.66       82.01
         26 |        283        2.83       84.84
         27 |        287        2.87       87.71
         28 |        390        3.90       91.61
         29 |        248        2.48       94.09
         30 |        290        2.90       96.99
         31 |         65        0.65       97.64
         99 |        236        2.36      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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