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

 Model Year |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |          1        0.01        0.01
         33 |          1        0.01        0.02
         35 |          1        0.01        0.03
         37 |          1        0.01        0.04
         41 |          1        0.01        0.05
         45 |          1        0.01        0.06
         46 |          4        0.04        0.10
         47 |          4        0.04        0.14
         48 |          5        0.05        0.19
         49 |          9        0.09        0.28
         50 |         12        0.12        0.40
         51 |         14        0.14        0.54
         52 |          8        0.08        0.62
         53 |         12        0.12        0.74
         54 |         11        0.11        0.85
         55 |         28        0.28        1.13
         56 |         22        0.22        1.35
         57 |         26        0.26        1.61
         58 |         28        0.28        1.89
         59 |         48        0.48        2.37
         60 |         60        0.60        2.97
         61 |         59        0.59        3.56
         62 |        110        1.10        4.66
         63 |        169        1.69        6.35
         64 |        243        2.43        8.78
         65 |        293        2.93       11.71
         66 |        337        3.37       15.08
         67 |        375        3.75       18.83
         68 |        463        4.63       23.46
         69 |        624        6.24       29.70
         70 |        569        5.69       35.39
         71 |        692        6.92       42.31
         72 |        717        7.17       49.48
         73 |        864        8.64       58.12
         74 |        813        8.13       66.25
         75 |        660        6.60       72.85
         76 |        768        7.68       80.53
         77 |      1,013       10.13       90.66
         78 |        811        8.11       98.77
         79 |         26        0.26       99.03
         99 |         97        0.97      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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