Frequencies for first 10,000 rows of cntocpop variable in natl1995 dataset :

 Population |
    Size of |
  County of |
 Occurrence |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,466       24.66       24.66
          2 |        602        6.02       30.68
          3 |      2,920       29.20       59.88
          9 |      4,012       40.12      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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