Frequencies for first 10,000 rows of pct012k157 variable in sf12010880us30 dataset :

   50 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      8,986       89.86       89.86
          1 |        765        7.65       97.51
          2 |        156        1.56       99.07
          3 |         55        0.55       99.62
          4 |         16        0.16       99.78
          5 |          8        0.08       99.86
          6 |          7        0.07       99.93
          7 |          2        0.02       99.95
          8 |          1        0.01       99.96
          9 |          1        0.01       99.97
         10 |          2        0.02       99.99
         22 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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