Year % change from 1990 1991 -1.3856610482836 1992 -3.03192585311892 1993 -5.02442742692853 1994 -5.86810631197221 1995 -7.69190235139566 1996 -7.61191736522856 1997 -9.32860428834433 1998 -7.95091468907931 1999 -11.2163275214786 2000 -10.6021643887621 2001 -10.6582990577573 2002 -10.4820255386106 2003 -9.34814436767745 2004 -10.4545486187712 2005 -10.8094088428828 2006 -10.7410094091573 2007 -9.68872368876576 2008 -9.7091793352773 2009 -10.8152032030299 2010 -9.8631244390914 2011 -9.97751522723078 2012 -10.3137280804575