Frequencies for first 10,000 rows of birday variable in natl1981 dataset :

 Birth Date |
      - Day |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        409        4.09        4.09
          2 |        370        3.70        7.79
          3 |        425        4.25       12.04
          4 |        370        3.70       15.74
          5 |        353        3.53       19.27
          6 |        379        3.79       23.06
          7 |        383        3.83       26.89
          8 |        323        3.23       30.12
          9 |        342        3.42       33.54
         10 |        342        3.42       36.96
         11 |        339        3.39       40.35
         12 |        340        3.40       43.75
         13 |        364        3.64       47.39
         14 |        294        2.94       50.33
         15 |        352        3.52       53.85
         16 |        361        3.61       57.46
         17 |        321        3.21       60.67
         18 |        328        3.28       63.95
         19 |        317        3.17       67.12
         20 |        340        3.40       70.52
         21 |        335        3.35       73.87
         22 |        300        3.00       76.87
         23 |        345        3.45       80.32
         24 |        273        2.73       83.05
         25 |        274        2.74       85.79
         26 |        285        2.85       88.64
         27 |        313        3.13       91.77
         28 |        297        2.97       94.74
         29 |        183        1.83       96.57
         30 |        179        1.79       98.36
         31 |        164        1.64      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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