Frequencies for first 10,000 rows of pct012k138 variable in sf12010880us30 dataset :

   31 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,322       93.22       93.22
          1 |        515        5.15       98.37
          2 |        111        1.11       99.48
          3 |         34        0.34       99.82
          4 |         10        0.10       99.92
          5 |          4        0.04       99.96
          6 |          1        0.01       99.97
          8 |          1        0.01       99.98
          9 |          1        0.01       99.99
         16 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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