Frequencies for first 10,000 rows of episode variable in nhamcsopd2002 dataset :

episode of care |      Freq.     Percent        Cum.
----------------+-----------------------------------
          Blank |        624        6.24        6.24
  Initial visit |      1,964       19.64       25.88
Follow-up visit |      4,819       48.19       74.07
        Unknown |        155        1.55       75.62
 Not applicable |      2,438       24.38      100.00
----------------+-----------------------------------
          Total |     10,000      100.00

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