Frequencies for first 10,000 rows of unkins variable in namcs1995 dataset :

    unknown |
  insurance |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,440       94.40       94.40
          1 |        560        5.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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