Frequencies for pvin_9 variable in parkwork dataset :

        vin |
character(9 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          2        0.17        0.17
          0 |        113        9.86       10.03
          1 |        104        9.08       19.11
          2 |         95        8.29       27.40
          3 |        100        8.73       36.13
          4 |         90        7.85       43.98
          5 |         93        8.12       52.09
          6 |         95        8.29       60.38
          7 |        105        9.16       69.55
          8 |         91        7.94       77.49
          9 |        158       13.79       91.27
          V |          1        0.09       91.36
          X |         99        8.64      100.00
------------+-----------------------------------
      Total |      1,146      100.00

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