Frequencies for first 10,000 rows of cntynat variable in natl1999 dataset :

NCHS County |
         of |
  Occurence |      Freq.     Percent        Cum.
------------+-----------------------------------
      01008 |        311        3.11        3.11
      01037 |      2,282       22.82       25.93
      01045 |        815        8.15       34.08
      01049 |      1,177       11.77       45.85
      01051 |      1,021       10.21       56.06
      01052 |        354        3.54       59.60
      01063 |        545        5.45       65.05
      01999 |      3,495       34.95      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015