Frequencies for first 10,000 rows of vmonth variable in nhamcsed1996 dataset :

   month of |
      visit |      Freq.     Percent        Cum.
------------+-----------------------------------
    January |        877        8.77        8.77
   February |        676        6.76       15.53
      March |        812        8.12       23.65
      April |        834        8.34       31.99
        May |        884        8.84       40.83
       June |        747        7.47       48.30
       July |        970        9.70       58.00
     August |        875        8.75       66.75
  September |        822        8.22       74.97
    October |        900        9.00       83.97
   November |        792        7.92       91.89
   December |        811        8.11      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016