Frequencies for first 10,000 rows of pct012e147 variable in sf12000860us20 dataset :

   40 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,696       96.96       96.96
          1 |        278        2.78       99.74
          2 |         22        0.22       99.96
          3 |          4        0.04      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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