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

 Model Year |      Freq.     Percent        Cum.
------------+-----------------------------------
         12 |          1        0.01        0.01
         36 |          1        0.01        0.02
         42 |          1        0.01        0.03
         47 |          2        0.02        0.05
         48 |          2        0.02        0.07
         49 |          5        0.05        0.12
         50 |          5        0.05        0.17
         51 |          4        0.04        0.21
         52 |          3        0.03        0.24
         53 |          7        0.07        0.31
         54 |          3        0.03        0.34
         55 |          5        0.05        0.39
         56 |         12        0.12        0.51
         57 |          8        0.08        0.59
         58 |          7        0.07        0.66
         59 |          6        0.06        0.72
         60 |         23        0.23        0.95
         61 |         17        0.17        1.12
         62 |         31        0.31        1.43
         63 |         51        0.51        1.94
         64 |         59        0.59        2.53
         65 |         79        0.79        3.32
         66 |        115        1.15        4.47
         67 |        122        1.22        5.69
         68 |        159        1.59        7.28
         69 |        193        1.93        9.21
         70 |        224        2.24       11.45
         71 |        259        2.59       14.04
         72 |        349        3.49       17.53
         73 |        439        4.39       21.92
         74 |        435        4.35       26.27
         75 |        386        3.86       30.13
         76 |        491        4.91       35.04
         77 |        556        5.56       40.60
         78 |        716        7.16       47.76
         79 |        698        6.98       54.74
         80 |        575        5.75       60.49
         81 |        577        5.77       66.26
         82 |        669        6.69       72.95
         83 |        642        6.42       79.37
         84 |        941        9.41       88.78
         85 |        757        7.57       96.35
         86 |         51        0.51       96.86
         99 |        314        3.14      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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