Frequencies for first 10,000 rows of pct012e023 variable in sf12000860us20 dataset :

   20 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,561       95.61       95.61
          1 |        336        3.36       98.97
          2 |         72        0.72       99.69
          3 |         17        0.17       99.86
          4 |          9        0.09       99.95
          5 |          2        0.02       99.97
          6 |          1        0.01       99.98
          7 |          1        0.01       99.99
         11 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2017