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

        Are |
admitted ED |
   patients |
       ever |
  'boarded' |
   for more |
     than 2 |
   hours in |
  the ED or |
      obser |      Freq.     Percent        Cum.
------------+-----------------------------------
      Blank |         98        0.98        0.98
    Unknown |        601        6.01        6.99
        Yes |      7,595       75.95       82.94
         No |      1,706       17.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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