Frequencies for first 10,000 rows of vmonth variable in namcs2011 dataset :

   Month of |
      Visit |      Freq.     Percent        Cum.
------------+-----------------------------------
    January |      1,087       10.87       10.87
   February |        763        7.63       18.50
      March |      1,109       11.09       29.59
      April |        941        9.41       39.00
        May |        836        8.36       47.36
       June |        777        7.77       55.13
       July |        936        9.36       64.49
     August |        984        9.84       74.33
  September |        496        4.96       79.29
    October |        573        5.73       85.02
   November |        675        6.75       91.77
   December |        823        8.23      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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