Frequencies for first 10,000 rows of cityres variable in natl1977 dataset :

  NCHS City |
         of |
  Residence |      Freq.     Percent        Cum.
------------+-----------------------------------
        021 |        743        7.43        7.43
        066 |          1        0.01        7.44
        078 |          1        0.01        7.45
        294 |          1        0.01        7.46
        999 |      9,254       92.54      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016