Frequencies for first 10,000 rows of vin_9 variable in vehicle dataset :

      vin_9 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |         22        0.22        0.22
          0 |        957        9.57        9.79
          1 |        883        8.83       18.62
          2 |        853        8.53       27.15
          3 |        860        8.60       35.75
          4 |        851        8.51       44.26
          5 |        831        8.31       52.57
          6 |        903        9.03       61.60
          7 |        907        9.07       70.67
          8 |        898        8.98       79.65
          9 |      1,229       12.29       91.94
          A |          1        0.01       91.95
          B |          1        0.01       91.96
          C |          3        0.03       91.99
          E |          1        0.01       92.00
          L |          3        0.03       92.03
          N |          2        0.02       92.05
          O |          1        0.01       92.06
          P |          1        0.01       92.07
          R |          2        0.02       92.09
          V |          1        0.01       92.10
          X |        788        7.88       99.98
          Y |          1        0.01       99.99
          Z |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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