Frequencies for first 10,000 rows of cntyres variable in natlterr1995 dataset :

NCHS County |
         of |
  Residence |      Freq.     Percent        Cum.
------------+-----------------------------------
      10000 |          3        0.03        0.03
      33000 |          1        0.01        0.04
      52011 |        524        5.24        5.28
      52013 |        368        3.68        8.96
      52016 |        467        4.67       13.63
      52050 |        284        2.84       16.47
      52058 |        575        5.75       22.22
      52065 |      1,089       10.89       33.11
      52999 |      6,684       66.84       99.95
      53999 |          3        0.03       99.98
      59ZZZ |          2        0.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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