Frequencies for pcarbur variable in parkwork dataset :

carburetion |      Freq.     Percent        Cum.
------------+-----------------------------------
            |        521       47.75       47.75
          1 |          1        0.09       47.85
          2 |          5        0.46       48.30
          3 |          1        0.09       48.40
          4 |          1        0.09       48.49
          F |        546       50.05       98.53
          T |         14        1.28       99.82
          Z |          2        0.18      100.00
------------+-----------------------------------
      Total |      1,091      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016