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

      FIRST |
ACCIDENT-YE |
         AR |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,467       54.67       54.67
       2000 |        655        6.55       61.22
       2001 |      1,534       15.34       76.56
       2002 |      1,248       12.48       89.04
       2003 |        546        5.46       94.50
       9999 |        469        4.69       99.19
          . |         81        0.81      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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