2006 1,132 vehicles 2005 1,533 vehicles 2004 1,870 vehicles 2003 2,439 vehicles 2002 2,730 vehicles 2001 2,886 vehicles 2000 1,783 vehicles 1999 815 vehicles 1998 1,984 vehicles 1997 3,327 vehicles 1996 4,157 vehicles 1995 4,034 vehicles 1994 3,375 vehicles 1993 3,004 vehicles 1992 2,523 vehicles 1991 1,506 vehicles 1990 544 vehicles