Frequencies for first 10,000 rows of vmonth variable in namcs2004 dataset :

   month of |
      visit |      Freq.     Percent        Cum.
------------+-----------------------------------
    January |      1,953       19.53       19.53
   February |      2,077       20.77       40.30
      March |      1,755       17.55       57.85
      April |        675        6.75       64.60
        May |        573        5.73       70.33
       June |        730        7.30       77.63
       July |        609        6.09       83.72
     August |        363        3.63       87.35
  September |        323        3.23       90.58
    October |        145        1.45       92.03
   November |        310        3.10       95.13
   December |        487        4.87      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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