Frequencies for first 10,000 rows of birday variable in natl1975 dataset :

 Birth Date |
      - Day |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        341        3.41        3.41
          2 |        316        3.16        6.57
          3 |        367        3.67       10.24
          4 |        332        3.32       13.56
          5 |        330        3.30       16.86
          6 |        356        3.56       20.42
          7 |        348        3.48       23.90
          8 |        337        3.37       27.27
          9 |        320        3.20       30.47
         10 |        362        3.62       34.09
         11 |        335        3.35       37.44
         12 |        329        3.29       40.73
         13 |        316        3.16       43.89
         14 |        347        3.47       47.36
         15 |        319        3.19       50.55
         16 |        330        3.30       53.85
         17 |        342        3.42       57.27
         18 |        328        3.28       60.55
         19 |        326        3.26       63.81
         20 |        361        3.61       67.42
         21 |        334        3.34       70.76
         22 |        303        3.03       73.79
         23 |        329        3.29       77.08
         24 |        320        3.20       80.28
         25 |        325        3.25       83.53
         26 |        327        3.27       86.80
         27 |        357        3.57       90.37
         28 |        333        3.33       93.70
         29 |        242        2.42       96.12
         30 |        203        2.03       98.15
         31 |        184        1.84       99.99
         99 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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