Frequencies for first 10,000 rows of vmonth variable in namcs2009 dataset :

   month of |
      visit |      Freq.     Percent        Cum.
------------+-----------------------------------
    january |        773        7.73        7.73
   february |        960        9.60       17.33
      march |        891        8.91       26.24
      april |      1,032       10.32       36.56
        may |        912        9.12       45.68
       june |      1,015       10.15       55.83
       july |        719        7.19       63.02
     august |        654        6.54       69.56
  september |        819        8.19       77.75
    october |        854        8.54       86.29
   november |        707        7.07       93.36
   december |        664        6.64      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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