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

 Model Year |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         14        0.14        0.14
         29 |          1        0.01        0.15
         39 |          1        0.01        0.16
         40 |          2        0.02        0.18
         41 |          1        0.01        0.19
         43 |          1        0.01        0.20
         46 |          9        0.09        0.29
         47 |          4        0.04        0.33
         48 |          2        0.02        0.35
         49 |          7        0.07        0.42
         50 |          1        0.01        0.43
         51 |          6        0.06        0.49
         52 |         11        0.11        0.60
         53 |          6        0.06        0.66
         54 |          9        0.09        0.75
         55 |         26        0.26        1.01
         56 |         33        0.33        1.34
         57 |         15        0.15        1.49
         58 |         19        0.19        1.68
         59 |         19        0.19        1.87
         60 |         35        0.35        2.22
         61 |         38        0.38        2.60
         62 |        109        1.09        3.69
         63 |         81        0.81        4.50
         64 |        192        1.92        6.42
         65 |        226        2.26        8.68
         66 |        255        2.55       11.23
         67 |        305        3.05       14.28
         68 |        387        3.87       18.15
         69 |        443        4.43       22.58
         70 |        508        5.08       27.66
         71 |        530        5.30       32.96
         72 |        661        6.61       39.57
         73 |        744        7.44       47.01
         74 |        687        6.87       53.88
         75 |        549        5.49       59.37
         76 |        728        7.28       66.65
         77 |        825        8.25       74.90
         78 |      1,029       10.29       85.19
         79 |        608        6.08       91.27
         80 |         13        0.13       91.40
         99 |         79        0.79       92.19
          . |        781        7.81      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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