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

 Model Year |      Freq.     Percent        Cum.
------------+-----------------------------------
         40 |          1        0.01        0.01
         42 |          1        0.01        0.02
         46 |          1        0.01        0.03
         47 |          2        0.02        0.05
         48 |          2        0.02        0.07
         49 |          2        0.02        0.09
         51 |          3        0.03        0.12
         52 |          1        0.01        0.13
         53 |          6        0.06        0.19
         54 |          3        0.03        0.22
         55 |          5        0.05        0.27
         56 |         11        0.11        0.38
         57 |          3        0.03        0.41
         58 |          2        0.02        0.43
         59 |          6        0.06        0.49
         60 |          9        0.09        0.58
         61 |          5        0.05        0.63
         62 |         13        0.13        0.76
         63 |         23        0.23        0.99
         64 |         36        0.36        1.35
         65 |         49        0.49        1.84
         66 |         49        0.49        2.33
         67 |         58        0.58        2.91
         68 |         83        0.83        3.74
         69 |        102        1.02        4.76
         70 |        102        1.02        5.78
         71 |        129        1.29        7.07
         72 |        209        2.09        9.16
         73 |        216        2.16       11.32
         74 |        248        2.48       13.80
         75 |        215        2.15       15.95
         76 |        278        2.78       18.73
         77 |        454        4.54       23.27
         78 |        514        5.14       28.41
         79 |        550        5.50       33.91
         80 |        472        4.72       38.63
         81 |        471        4.71       43.34
         82 |        422        4.22       47.56
         83 |        467        4.67       52.23
         84 |        643        6.43       58.66
         85 |        700        7.00       65.66
         86 |        766        7.66       73.32
         87 |        786        7.86       81.18
         88 |        909        9.09       90.27
         89 |        644        6.44       96.71
         90 |         31        0.31       97.02
         99 |        298        2.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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