Frequencies for first 10,000 rows of cntyres variable in natl1991 dataset :

NCHS County |
         of |
  Residence |      Freq.     Percent        Cum.
------------+-----------------------------------
      01008 |        379        3.79        3.79
      01028 |        237        2.37        6.16
      01037 |      1,917       19.17       25.33
      01045 |        783        7.83       33.16
      01049 |        210        2.10       35.26
      01051 |        689        6.89       42.15
      01063 |        224        2.24       44.39
      01999 |      5,423       54.23       98.62
      04999 |          1        0.01       98.63
      05030 |          1        0.01       98.64
      10017 |          2        0.02       98.66
      10046 |          1        0.01       98.67
      10053 |          2        0.02       98.69
      10999 |         53        0.53       99.22
      11025 |          1        0.01       99.23
      11060 |          1        0.01       99.24
      11999 |         24        0.24       99.48
      12002 |          1        0.01       99.49
      18056 |          1        0.01       99.50
      18999 |          1        0.01       99.51
      25024 |          1        0.01       99.52
      25030 |          2        0.02       99.54
      25999 |          7        0.07       99.61
      33039 |          1        0.01       99.62
      37016 |          1        0.01       99.63
      41002 |          1        0.01       99.64
      43019 |          1        0.01       99.65
      43999 |         33        0.33       99.98
      44220 |          1        0.01       99.99
      47058 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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