Frequencies for first 10,000 rows of month variable in person dataset :

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,375       13.75       13.75
          2 |      1,314       13.14       26.89
          3 |      1,423       14.23       41.12
          4 |        859        8.59       49.71
          5 |        619        6.19       55.90
          6 |        678        6.78       62.68
          7 |        741        7.41       70.09
          8 |        599        5.99       76.08
          9 |        671        6.71       82.79
         10 |        616        6.16       88.95
         11 |        591        5.91       94.86
         12 |        514        5.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016