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

      FIRST |
ACCIDENT-YE |
         AR |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,238       52.38       52.38
       2004 |        684        6.84       59.22
       2005 |      1,578       15.78       75.00
       2006 |      1,342       13.42       88.42
       2007 |        558        5.58       94.00
       9999 |        553        5.53       99.53
          . |         47        0.47      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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