Frequencies for first 10,000 rows of ocntypop variable in natlterr2005 dataset :

  Occurence |
     County |
 Population |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      3,053       30.53       30.53
          2 |      1,026       10.26       40.79
          3 |      4,714       47.14       87.93
          9 |      1,207       12.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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