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

      vin_9 |      Freq.     Percent        Cum.
------------+-----------------------------------
            |         35        0.35        0.35
          0 |        898        8.98        9.33
          1 |        898        8.98       18.31
          2 |        868        8.68       26.99
          3 |        822        8.22       35.21
          4 |        917        9.17       44.38
          5 |        873        8.73       53.11
          6 |        878        8.78       61.89
          7 |        861        8.61       70.50
          8 |        810        8.10       78.60
          9 |      1,297       12.97       91.57
          C |          1        0.01       91.58
          D |          1        0.01       91.59
          J |          1        0.01       91.60
          L |          2        0.02       91.62
          O |          3        0.03       91.65
          S |          3        0.03       91.68
          T |          1        0.01       91.69
          X |        829        8.29       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