Frequencies for first 10,000 rows of episode variable in nhamcsopd2003 dataset :

episode of care |      Freq.     Percent        Cum.
----------------+-----------------------------------
          blank |        235        2.35        2.35
  initial visit |      2,649       26.49       28.84
follow-up visit |      4,959       49.59       78.43
        unknown |        188        1.88       80.31
 not applicable |      1,969       19.69      100.00
----------------+-----------------------------------
          Total |     10,000      100.00

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