Frequencies for first 10,000 rows of pct012m040 variable in sf12010880us32 dataset :

   37 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,859       98.59       98.59
          1 |        127        1.27       99.86
          2 |         11        0.11       99.97
          3 |          3        0.03      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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