Year % change from 1990 1991 -23.3521252642615 1992 -45.4337899543379 1993 -41.4152959442659 1994 -33.9254510349885 1995 -41.5295944265883 1996 -30.7445729705574 1997 -32.1210246185754 1998 -30.3452444383332 1999 -32.0305025122749 2000 -25.9248437347817 2001 -32.7904871578923 2002 -40.9031012415279 2003 -41.6533461668471 2004 -33.6604733504065 2005 -35.6702932801659 2006 -40.1757733051454 2007 -47.9649713824101 2008 -55.4221595824525 2009 -58.7729098273778 2010 -61.0405458826765 2011 -60.3920853901609 2012 -59.7436248976453