Frequencies for first 10,000 rows of cityres variable in natl1969 dataset :

  NCHS City |
         of |
  Residence |      Freq.     Percent        Cum.
------------+-----------------------------------
        004 |          2        0.02        0.02
        006 |        977        9.77        9.79
        010 |          2        0.02        9.81
        017 |          1        0.01        9.82
        018 |          1        0.01        9.83
        020 |          1        0.01        9.84
        021 |          1        0.01        9.85
        032 |          1        0.01        9.86
        069 |          1        0.01        9.87
        999 |      9,013       90.13      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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