Frequencies for pvin_3 variable in parkwork dataset :

        vin |
character(3 |
          ) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         10        0.87        0.87
          1 |        115       10.03       10.91
          2 |         33        2.88       13.79
          3 |         58        5.06       18.85
          4 |        107        9.34       28.18
          5 |          3        0.26       28.45
          6 |         21        1.83       30.28
          7 |         29        2.53       32.81
          8 |         35        3.05       35.86
          9 |         52        4.54       40.40
          A |         80        6.98       47.38
          B |         24        2.09       49.48
          C |         33        2.88       52.36
          D |         60        5.24       57.59
          E |         19        1.66       59.25
          F |          7        0.61       59.86
          G |         48        4.19       64.05
          H |         19        1.66       65.71
          J |          5        0.44       66.14
          K |         43        3.75       69.90
          L |          9        0.79       70.68
          M |         67        5.85       76.53
          N |         57        4.97       81.50
          P |         15        1.31       82.81
          R |          6        0.52       83.33
          S |         18        1.57       84.90
          T |         88        7.68       92.58
          U |         37        3.23       95.81
          V |         12        1.05       96.86
          W |         17        1.48       98.34
          X |         12        1.05       99.39
          Y |          4        0.35       99.74
          Z |          3        0.26      100.00
------------+-----------------------------------
      Total |      1,146      100.00

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