Frequencies for first 10,000 rows of episode variable in nhamcsed2001 dataset :

episode of care |      Freq.     Percent        Cum.
----------------+-----------------------------------
          Blank |        396        3.96        3.96
  Initial visit |      8,523       85.23       89.19
Follow-up visit |        648        6.48       95.67
        Unknown |        433        4.33      100.00
----------------+-----------------------------------
          Total |     10,000      100.00

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