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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,369       13.69       13.69
          2 |      1,148       11.48       25.17
          3 |      1,495       14.95       40.12
          4 |        972        9.72       49.84
          5 |        688        6.88       56.72
          6 |        650        6.50       63.22
          7 |        622        6.22       69.44
          8 |        577        5.77       75.21
          9 |        506        5.06       80.27
         10 |        668        6.68       86.95
         11 |        664        6.64       93.59
         12 |        641        6.41      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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