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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,322       13.22       13.22
          2 |      1,221       12.21       25.43
          3 |      1,235       12.35       37.78
          4 |      1,003       10.03       47.81
          5 |        640        6.40       54.21
          6 |        688        6.88       61.09
          7 |        627        6.27       67.36
          8 |        746        7.46       74.82
          9 |        619        6.19       81.01
         10 |        691        6.91       87.92
         11 |        598        5.98       93.90
         12 |        610        6.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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