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

       LAST |
ACCIDENT-YE |
         AR |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      5,421       54.21       54.21
       1996 |        279        2.79       57.00
       1997 |        956        9.56       66.56
       1998 |      1,638       16.38       82.94
       1999 |      1,255       12.55       95.49
       9999 |        399        3.99       99.48
          . |         52        0.52      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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