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

      FIRST |
ACCIDENT-YE |
         AR |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,464       54.64       54.64
       1999 |        691        6.91       61.55
       2000 |      1,518       15.18       76.73
       2001 |      1,248       12.48       89.21
       2002 |        556        5.56       94.77
       9999 |        471        4.71       99.48
          . |         52        0.52      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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