Frequencies for first 10,000 rows of cntrspop variable in natl1992 dataset :

 Population |
    Size of |
  County of |
  Residence |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |          2        0.02        0.02
          1 |      1,705       17.05       17.07
          2 |      1,168       11.68       28.75
          3 |      2,121       21.21       49.96
          9 |      5,003       50.03       99.99
          Z |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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