Frequencies for first 10,000 rows of surgday variable in nhamcsed2013 dataset :

  Number of |
  days in a |
       week |
   elective |
  surgeries |
  scheduled |      Freq.     Percent        Cum.
------------+-----------------------------------
    Unknown |        725        7.25        7.25
          1 |         90        0.90        8.15
          5 |      6,667       66.67       74.82
          6 |      1,805       18.05       92.87
          7 |        713        7.13      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016