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

 Model Year |      Freq.     Percent        Cum.
------------+-----------------------------------
         29 |          2        0.02        0.02
         32 |          5        0.05        0.07
         40 |          1        0.01        0.08
         41 |          2        0.02        0.10
         42 |          2        0.02        0.12
         47 |          2        0.02        0.14
         48 |          3        0.03        0.17
         49 |          4        0.04        0.21
         50 |         14        0.14        0.35
         51 |          3        0.03        0.38
         52 |          1        0.01        0.39
         53 |          3        0.03        0.42
         54 |          2        0.02        0.44
         55 |         20        0.20        0.64
         56 |         20        0.20        0.84
         57 |         17        0.17        1.01
         58 |          7        0.07        1.08
         59 |          7        0.07        1.15
         60 |         22        0.22        1.37
         61 |         15        0.15        1.52
         62 |         29        0.29        1.81
         63 |         54        0.54        2.35
         64 |         84        0.84        3.19
         65 |        103        1.03        4.22
         66 |        163        1.63        5.85
         67 |        165        1.65        7.50
         68 |        204        2.04        9.54
         69 |        279        2.79       12.33
         70 |        317        3.17       15.50
         71 |        290        2.90       18.40
         72 |        528        5.28       23.68
         73 |        586        5.86       29.54
         74 |        475        4.75       34.29
         75 |        401        4.01       38.30
         76 |        642        6.42       44.72
         77 |        591        5.91       50.63
         78 |        830        8.30       58.93
         79 |        748        7.48       66.41
         80 |        578        5.78       72.19
         81 |        718        7.18       79.37
         82 |        628        6.28       85.65
         83 |        450        4.50       90.15
         84 |         16        0.16       90.31
         99 |        149        1.49       91.80
          . |        820        8.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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