Frequencies for first 10,000 rows of vday variable in nhamcsopd1995 dataset :

     day of |
    visit - |
       1-31 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        303        3.03        3.03
          2 |        255        2.55        5.58
          3 |        323        3.23        8.81
          4 |        262        2.62       11.43
          5 |        365        3.65       15.08
          6 |        368        3.68       18.76
          7 |        327        3.27       22.03
          8 |        317        3.17       25.20
          9 |        314        3.14       28.34
         10 |        345        3.45       31.79
         11 |        332        3.32       35.11
         12 |        376        3.76       38.87
         13 |        433        4.33       43.20
         14 |        352        3.52       46.72
         15 |        273        2.73       49.45
         16 |        308        3.08       52.53
         17 |        379        3.79       56.32
         18 |        357        3.57       59.89
         19 |        360        3.60       63.49
         20 |        402        4.02       67.51
         21 |        309        3.09       70.60
         22 |        275        2.75       73.35
         23 |        242        2.42       75.77
         24 |        306        3.06       78.83
         25 |        268        2.68       81.51
         26 |        291        2.91       84.42
         27 |        470        4.70       89.12
         28 |        341        3.41       92.53
         29 |        268        2.68       95.21
         30 |        266        2.66       97.87
         31 |        213        2.13      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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