2006 1,487 vehicles 2005 2,681 vehicles 2004 4,178 vehicles 2003 5,266 vehicles 2002 5,978 vehicles 2001 6,851 vehicles 2000 5,352 vehicles 1999 2,708 vehicles 1998 3,039 vehicles 1997 3,364 vehicles 1996 4,326 vehicles 1995 4,458 vehicles 1994 5,832 vehicles 1993 2,379 vehicles 1992 2,373 vehicles 1991 3,159 vehicles 1990 3,289 vehicles 1989 863 vehicles 1988 584 vehicles 1987 466 vehicles 1986 348 vehicles 1985 266 vehicles 1984 209 vehicles 1983 220 vehicles 1982 202 vehicles 1981 160 vehicles 1980 210 vehicles