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

Episode of care |      Freq.     Percent        Cum.
----------------+-----------------------------------
          Blank |        207        2.07        2.07
        Unknown |        439        4.39        6.46
  Initial visit |      8,751       87.51       93.97
Follow-up visit |        603        6.03      100.00
----------------+-----------------------------------
          Total |     10,000      100.00

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