Frequencies for first 10,000 rows of diagsc1 variable in nhamcsopd1996 dataset :

      other |
diag/screen |
 service #1 |
    - 4 dgt |      Freq.     Percent        Cum.
------------+-----------------------------------
       0000 |      9,998       99.98       99.98
       0919 |          1        0.01       99.99
       8840 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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