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

 MODEL YEAR |      Freq.     Percent        Cum.
------------+-----------------------------------
         34 |          1        0.01        0.01
         38 |          1        0.01        0.02
         46 |          1        0.01        0.03
         47 |          1        0.01        0.04
         48 |          1        0.01        0.05
         50 |          3        0.03        0.08
         51 |          1        0.01        0.09
         52 |          1        0.01        0.10
         53 |          4        0.04        0.14
         54 |          2        0.02        0.16
         55 |          4        0.04        0.20
         56 |          3        0.03        0.23
         57 |          6        0.06        0.29
         58 |          3        0.03        0.32
         59 |          6        0.06        0.38
         60 |          7        0.07        0.45
         61 |          7        0.07        0.52
         62 |          8        0.08        0.60
         63 |         19        0.19        0.79
         64 |         33        0.33        1.12
         65 |         41        0.41        1.53
         66 |         25        0.25        1.78
         67 |         28        0.28        2.06
         68 |         40        0.40        2.46
         69 |         64        0.64        3.10
         70 |         85        0.85        3.95
         71 |         72        0.72        4.67
         72 |        100        1.00        5.67
         73 |        113        1.13        6.80
         74 |        112        1.12        7.92
         75 |        104        1.04        8.96
         76 |        182        1.82       10.78
         77 |        288        2.88       13.66
         78 |        308        3.08       16.74
         79 |        374        3.74       20.48
         80 |        301        3.01       23.49
         81 |        338        3.38       26.87
         82 |        380        3.80       30.67
         83 |        412        4.12       34.79
         84 |        583        5.83       40.62
         85 |        567        5.67       46.29
         86 |        656        6.56       52.85
         87 |        639        6.39       59.24
         88 |        677        6.77       66.01
         89 |        720        7.20       73.21
         90 |        620        6.20       79.41
         91 |        612        6.12       85.53
         92 |        593        5.93       91.46
         93 |        571        5.71       97.17
         94 |         39        0.39       97.56
         99 |        244        2.44      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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