Frequencies for pvin_6 variable in parkwork dataset :

        vin |
character(6 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          2        0.18        0.18
          0 |         49        4.32        4.50
          1 |        204       18.01       22.51
          2 |        125       11.03       33.54
          3 |        106        9.36       42.89
          4 |        125       11.03       53.93
          5 |        146       12.89       66.81
          6 |         63        5.56       72.37
          7 |         51        4.50       76.88
          8 |         29        2.56       79.44
          9 |         54        4.77       84.20
          A |         37        3.27       87.47
          B |         25        2.21       89.67
          C |          7        0.62       90.29
          D |          6        0.53       90.82
          E |          6        0.53       91.35
          F |          7        0.62       91.97
          G |          4        0.35       92.32
          H |          8        0.71       93.03
          J |          1        0.09       93.12
          K |          2        0.18       93.29
          L |         13        1.15       94.44
          M |          8        0.71       95.15
          N |          2        0.18       95.32
          P |          6        0.53       95.85
          R |          7        0.62       96.47
          S |         15        1.32       97.79
          T |          1        0.09       97.88
          U |          4        0.35       98.23
          V |          2        0.18       98.41
          W |          4        0.35       98.76
          X |          7        0.62       99.38
          Y |          1        0.09       99.47
          Z |          6        0.53      100.00
------------+-----------------------------------
      Total |      1,133      100.00

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