Frequencies for vin_bt variable in vehnit dataset :

     vin_bt |      Freq.     Percent        Cum.
------------+-----------------------------------
            |         14        0.95        0.95
         2D |         15        1.01        1.96
         2H |         21        1.42        3.38
         2P |          3        0.20        3.58
         2T |          2        0.14        3.71
         2W |          3        0.20        3.92
         3C |         12        0.81        4.73
         3D |          1        0.07        4.79
         3P |          3        0.20        5.00
         4B |          2        0.14        5.13
         4C |         39        2.63        7.77
         4D |        393       26.54       34.30
         4H |          9        0.61       34.91
         4P |          6        0.41       35.31
         4W |         32        2.16       37.47
         99 |        109        7.36       44.83
         BU |          4        0.27       45.10
         CB |         38        2.57       47.67
         CC |         44        2.97       50.64
         CG |         15        1.01       51.65
         CH |          2        0.14       51.79
         CP |         72        4.86       56.65
         CS |          1        0.07       56.72
         CV |         11        0.74       57.46
         CW |         30        2.03       59.49
         DP |          2        0.14       59.62
         DS |        112        7.56       67.18
         EC |          5        0.34       67.52
         ES |          1        0.07       67.59
         FB |          2        0.14       67.72
         FC |          1        0.07       67.79
         GG |          2        0.14       67.93
         IC |         13        0.88       68.80
         IE |          1        0.07       68.87
         MH |          1        0.07       68.94
         MY |          6        0.41       69.35
         PC |         40        2.70       72.05
         PK |        107        7.22       79.27
         PS |         18        1.22       80.49
         RD |          1        0.07       80.55
         RS |          4        0.27       80.82
         S2 |          1        0.07       80.89
         SD |          1        0.07       80.96
         SN |          2        0.14       81.09
         SV |         75        5.06       86.16
         SW |         29        1.96       88.12
         TB |         16        1.08       89.20
         TL |          1        0.07       89.26
         TM |         21        1.42       90.68
         UT |        127        8.58       99.26
         VN |          4        0.27       99.53
         YY |          7        0.47      100.00
------------+-----------------------------------
      Total |      1,481      100.00

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