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

      FIRST |
ACCIDENT-YE |
         AR |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,331       53.31       53.31
       2003 |        686        6.86       60.17
       2004 |      1,571       15.71       75.88
       2005 |      1,180       11.80       87.68
       2006 |        573        5.73       93.41
       9999 |        599        5.99       99.40
          . |         60        0.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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