Frequencies for pvin_3 variable in parkwork dataset :

        vin |
character(3 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          2        0.18        0.18
          0 |         14        1.24        1.41
          1 |        112        9.89       11.30
          2 |         33        2.91       14.21
          3 |         62        5.47       19.68
          4 |        135       11.92       31.60
          5 |          4        0.35       31.95
          6 |         22        1.94       33.89
          7 |         28        2.47       36.36
          8 |         36        3.18       39.54
          9 |         27        2.38       41.92
          A |         66        5.83       47.75
          B |         16        1.41       49.16
          C |         39        3.44       52.60
          D |         58        5.12       57.72
          E |         19        1.68       59.40
          F |          6        0.53       59.93
          G |         40        3.53       63.46
          H |         14        1.24       64.70
          J |          3        0.26       64.96
          K |         38        3.35       68.31
          L |          6        0.53       68.84
          M |         47        4.15       72.99
          N |         58        5.12       78.11
          P |         35        3.09       81.20
          R |          9        0.79       81.99
          S |         24        2.12       84.11
          T |         93        8.21       92.32
          U |         37        3.27       95.59
          V |         14        1.24       96.82
          W |         14        1.24       98.06
          X |         14        1.24       99.29
          Y |          5        0.44       99.74
          Z |          3        0.26      100.00
------------+-----------------------------------
      Total |      1,133      100.00

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