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

      month |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,132       11.32       11.32
          2 |      1,009       10.09       21.41
          3 |      1,041       10.41       31.82
          4 |      1,231       12.31       44.13
          5 |      1,162       11.62       55.75
          6 |        701        7.01       62.76
          7 |        720        7.20       69.96
          8 |        604        6.04       76.00
          9 |        617        6.17       82.17
         10 |        739        7.39       89.56
         11 |        478        4.78       94.34
         12 |        566        5.66      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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