Frequencies for first 10,000 rows of vmonth variable in namcs2012 dataset :

   Month of |
      visit |      Freq.     Percent        Cum.
------------+-----------------------------------
    January |        907        9.07        9.07
   February |        734        7.34       16.41
      March |        848        8.48       24.89
      April |        739        7.39       32.28
        May |        834        8.34       40.62
       June |        825        8.25       48.87
       July |        986        9.86       58.73
     August |        777        7.77       66.50
  September |      1,128       11.28       77.78
    October |        813        8.13       85.91
   November |        740        7.40       93.31
   December |        669        6.69      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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