Year % change from 1990 1991 -1.99508777237186 1992 -4.25690749320242 1993 -5.36890739493242 1994 -1.65471691562137 1995 -3.19612245139763 1996 0.561692154629956 1997 -1.68362059467471 1998 1.37025037322376 1999 -8.05386341403613 2000 -10.3747647024275 2001 -12.8972935298916 2002 -13.2898401859512 2003 -11.6620522701777 2004 -15.2765058993301 2005 -16.5394109560211 2006 -19.878602756495 2007 -18.09965519666 2008 -21.732307774847 2009 -23.0686592591871 2010 -24.3963627287634 2011 -25.0932134532625 2012 -25.761618690156