Frequencies for first 10,000 rows of enotdiso variable in nhamcsopd2006 dataset :

   if yes, are |
    notifiable |
 diseases sent |
electronically |
             ? |      Freq.     Percent        Cum.
---------------+-----------------------------------
           Yes |        196        1.96        1.96
            No |         58        0.58        2.54
       Unknown |         98        0.98        3.52
Not applicable |      3,970       39.70       43.22
         Blank |      5,678       56.78      100.00
---------------+-----------------------------------
         Total |     10,000      100.00

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