Frequencies for pvin_12 variable in parkwork dataset :

        VIN |
Character(1 |
         2) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          7        0.70        0.70
          0 |        135       13.47       14.17
          1 |        206       20.56       34.73
          2 |        121       12.08       46.81
          3 |         63        6.29       53.09
          4 |         51        5.09       58.18
          5 |         71        7.09       65.27
          6 |         60        5.99       71.26
          7 |         32        3.19       74.45
          8 |         33        3.29       77.74
          9 |         58        5.79       83.53
          A |         80        7.98       91.52
          B |         29        2.89       94.41
          C |         15        1.50       95.91
          D |          3        0.30       96.21
          E |          2        0.20       96.41
          F |          2        0.20       96.61
          G |          3        0.30       96.91
          J |          5        0.50       97.41
          K |          1        0.10       97.50
          L |          4        0.40       97.90
          M |          8        0.80       98.70
          N |          2        0.20       98.90
          P |          1        0.10       99.00
          R |          1        0.10       99.10
          S |          1        0.10       99.20
          V |          2        0.20       99.40
          W |          2        0.20       99.60
          X |          1        0.10       99.70
          Y |          1        0.10       99.80
          Z |          2        0.20      100.00
------------+-----------------------------------
      Total |      1,002      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016