Frequencies for di_hcc31 variable in hcccoefn dataset :

 intestinal |
obstruction |
   /perfora |      Freq.     Percent        Cum.
------------+-----------------------------------
       .057 |          1      100.00      100.00
------------+-----------------------------------
      Total |          1      100.00

by Jean Roth , jroth@nber.org , 2 May 2016