Year % change from 1990 1991 -16.3294318343364 1992 -20.7026252191632 1993 -38.7592996256456 1994 -20.1102923754916 1995 -22.592759323319 1996 -15.3982846040847 1997 -14.6691228735251 1998 -18.4428754205563 1999 -26.3635502061318 2000 -35.5310856276359 2001 -38.1853291001279 2002 -42.7421456664929 2003 -39.4677297066768 2004 -37.1582239492015 2005 -38.562052788703 2006 -36.3716059328058 2007 -40.6494337298015 2008 -39.4825380277686 2009 -36.9449841254798 2010 -35.4108420603706 2011 -41.9283385577538 2012 -46.9116929900276