Frequencies for first 10,000 rows of episode variable in nhamcsed2008 dataset :

episode of care |      Freq.     Percent        Cum.
----------------+-----------------------------------
          blank |        371        3.71        3.71
        unknown |        609        6.09        9.80
  initial visit |      8,276       82.76       92.56
follow-up visit |        744        7.44      100.00
----------------+-----------------------------------
          Total |     10,000      100.00

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