Frequencies for first 10,000 rows of vmonth variable in nhamcsed2000 dataset :

   month of |
      visit |      Freq.     Percent        Cum.
------------+-----------------------------------
    January |        959        9.59        9.59
   February |        867        8.67       18.26
      March |        692        6.92       25.18
      April |        951        9.51       34.69
        May |        843        8.43       43.12
       June |        900        9.00       52.12
       July |        974        9.74       61.86
     August |        680        6.80       68.66
  September |        672        6.72       75.38
    October |        872        8.72       84.10
   November |        613        6.13       90.23
   December |        977        9.77      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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