Frequencies for first 10,000 rows of pct012k187 variable in sf12010880us30 dataset :

   80 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,770       97.70       97.70
          1 |        203        2.03       99.73
          2 |         21        0.21       99.94
          3 |          5        0.05       99.99
         10 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 8 May 2017