Frequencies for first 10,000 rows of papunsp variable in namcs2009 dataset :

      pap - |
unspecified |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,944       99.44       99.44
        yes |         56        0.56      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016