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

 Population |
    Size of |
  County of |
  Residence |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |          1        0.01        0.01
          1 |      1,921       19.21       19.22
          2 |        213        2.13       21.35
          3 |      2,323       23.23       44.58
          9 |      5,542       55.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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