Frequencies for first 10,000 rows of lmpday variable in natl1991 dataset :

   Day Last |
     Normal |
     Menses |
      Began |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        476        4.76        4.76
          2 |        217        2.17        6.93
          3 |        253        2.53        9.46
          4 |        263        2.63       12.09
          5 |        328        3.28       15.37
          6 |        252        2.52       17.89
          7 |        269        2.69       20.58
          8 |        230        2.30       22.88
          9 |        202        2.02       24.90
         10 |        365        3.65       28.55
         11 |        207        2.07       30.62
         12 |        232        2.32       32.94
         13 |        242        2.42       35.36
         14 |        285        2.85       38.21
         15 |        636        6.36       44.57
         16 |        250        2.50       47.07
         17 |        233        2.33       49.40
         18 |        254        2.54       51.94
         19 |        204        2.04       53.98
         20 |        376        3.76       57.74
         21 |        205        2.05       59.79
         22 |        226        2.26       62.05
         23 |        239        2.39       64.44
         24 |        238        2.38       66.82
         25 |        360        3.60       70.42
         26 |        226        2.26       72.68
         27 |        222        2.22       74.90
         28 |        261        2.61       77.51
         29 |        155        1.55       79.06
         30 |        182        1.82       80.88
         31 |         93        0.93       81.81
         99 |      1,819       18.19      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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