Frequencies for first 10,000 rows of pct012k145 variable in sf12010880us30 dataset :

   38 years |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,207       92.07       92.07
          1 |        626        6.26       98.33
          2 |        114        1.14       99.47
          3 |         30        0.30       99.77
          4 |         13        0.13       99.90
          5 |          7        0.07       99.97
          6 |          1        0.01       99.98
          9 |          1        0.01       99.99
         21 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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