Frequencies for first 10,000 rows of pct012k039 variable in sf12010880us30 dataset :

   36 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,287       92.87       92.87
          1 |        569        5.69       98.56
          2 |         99        0.99       99.55
          3 |         24        0.24       99.79
          4 |          9        0.09       99.88
          5 |          4        0.04       99.92
          6 |          5        0.05       99.97
          7 |          2        0.02       99.99
         17 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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