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

 Model Year |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |          1        0.01        0.01
          8 |          1        0.01        0.02
         10 |          1        0.01        0.03
         30 |          1        0.01        0.04
         36 |          1        0.01        0.05
         38 |          1        0.01        0.06
         39 |          2        0.02        0.08
         40 |          2        0.02        0.10
         41 |          1        0.01        0.11
         42 |          4        0.04        0.15
         44 |          1        0.01        0.16
         45 |          1        0.01        0.17
         46 |          3        0.03        0.20
         47 |          5        0.05        0.25
         48 |          8        0.08        0.33
         49 |          8        0.08        0.41
         50 |         14        0.14        0.55
         51 |         12        0.12        0.67
         52 |         13        0.13        0.80
         53 |         10        0.10        0.90
         54 |         16        0.16        1.06
         55 |         37        0.37        1.43
         56 |         41        0.41        1.84
         57 |         37        0.37        2.21
         58 |         31        0.31        2.52
         59 |         53        0.53        3.05
         60 |         89        0.89        3.94
         61 |         85        0.85        4.79
         62 |        162        1.62        6.41
         63 |        228        2.28        8.69
         64 |        338        3.38       12.07
         65 |        430        4.30       16.37
         66 |        521        5.21       21.58
         67 |        531        5.31       26.89
         68 |        629        6.29       33.18
         69 |        693        6.93       40.11
         70 |        686        6.86       46.97
         71 |        740        7.40       54.37
         72 |        901        9.01       63.38
         73 |      1,011       10.11       73.49
         74 |      1,033       10.33       83.82
         75 |        809        8.09       91.91
         76 |        666        6.66       98.57
         77 |         22        0.22       98.79
         78 |          1        0.01       98.80
         79 |          1        0.01       98.81
         80 |          2        0.02       98.83
         99 |        117        1.17      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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