Frequencies for first 10,000 rows of pct012k071 variable in sf12010880us30 dataset :

   68 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,549       95.49       95.49
          1 |        393        3.93       99.42
          2 |         46        0.46       99.88
          3 |          7        0.07       99.95
          4 |          2        0.02       99.97
          6 |          2        0.02       99.99
          9 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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