Frequencies for pvin_2 variable in parkwork dataset :

        vin |
character(2 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |          2        0.18        0.18
          0 |          9        0.79        0.97
          1 |          3        0.26        1.24
          2 |          1        0.09        1.32
          4 |          1        0.09        1.41
          8 |          6        0.53        1.94
          9 |         31        2.74        4.68
          A |         28        2.47        7.15
          B |         42        3.71       10.86
          C |         48        4.24       15.09
          D |         48        4.24       19.33
          E |          1        0.09       19.42
          F |        229       20.21       39.63
          G |        208       18.36       57.99
          H |        105        9.27       67.26
          J |         23        2.03       69.29
          K |          4        0.35       69.64
          L |         14        1.24       70.87
          M |         37        3.27       74.14
          N |         95        8.38       82.52
          P |          6        0.53       83.05
          S |          9        0.79       83.85
          T |        101        8.91       92.76
          U |          2        0.18       92.94
          V |         38        3.35       96.29
          W |          1        0.09       96.38
          X |         32        2.82       99.21
          Y |          8        0.71       99.91
          Z |          1        0.09      100.00
------------+-----------------------------------
      Total |      1,133      100.00

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