Frequencies for pvin_5 variable in parkwork dataset :

        vin |
character(5 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |          5        0.46        0.46
          1 |          3        0.27        0.73
          2 |          2        0.18        0.92
          3 |          2        0.18        1.10
          4 |          4        0.37        1.47
          5 |          4        0.37        1.83
          6 |          3        0.27        2.11
          7 |          8        0.73        2.84
          8 |          1        0.09        2.93
          9 |         41        3.76        6.69
          A |         67        6.14       12.83
          B |         53        4.86       17.69
          C |         99        9.07       26.76
          D |         60        5.50       32.26
          E |         51        4.67       36.94
          F |         76        6.97       43.90
          G |         50        4.58       48.49
          H |         16        1.47       49.95
          J |         23        2.11       52.06
          K |         57        5.22       57.29
          L |         51        4.67       61.96
          M |         34        3.12       65.08
          N |         36        3.30       68.38
          P |         88        8.07       76.44
          R |         34        3.12       79.56
          S |         37        3.39       82.95
          T |         33        3.02       85.98
          U |         55        5.04       91.02
          V |         12        1.10       92.12
          W |         30        2.75       94.87
          X |         33        3.02       97.89
          Y |         20        1.83       99.73
          Z |          3        0.27      100.00
------------+-----------------------------------
      Total |      1,091      100.00

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