Frequencies for pvin_2 variable in parkwork dataset :

        vin |
character(2 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |          4        0.37        0.37
          1 |          4        0.37        0.73
          3 |          1        0.09        0.82
          5 |          2        0.18        1.01
          6 |          1        0.09        1.10
          8 |          3        0.27        1.37
          9 |         43        3.94        5.32
          A |         19        1.74        7.06
          B |         56        5.13       12.19
          C |         29        2.66       14.85
          D |         40        3.67       18.52
          E |          2        0.18       18.70
          F |        238       21.81       40.51
          G |        222       20.35       60.86
          H |         97        8.89       69.75
          J |         29        2.66       72.41
          K |          1        0.09       72.50
          L |          9        0.82       73.33
          M |         44        4.03       77.36
          N |         84        7.70       85.06
          P |          9        0.82       85.88
          S |         15        1.37       87.26
          T |         94        8.62       95.88
          U |          3        0.27       96.15
          V |         20        1.83       97.98
          W |          2        0.18       98.17
          X |         16        1.47       99.63
          Y |          4        0.37      100.00
------------+-----------------------------------
      Total |      1,091      100.00

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