Year % change from 1990 1991 -23.8456454903313 1992 24.9926730454271 1993 -40.345372525357 1994 -23.6807171795535 1995 -15.7630089360113 1996 -32.6822400367784 1997 -35.944602476798 1998 -51.2891992069649 1999 -50.6920093095423 2000 -53.7101973967761 2001 -22.1906157515157 2002 -11.6041720541333 2003 -49.765422521047 2004 -48.6981582047525 2005 -43.2399505789731 2006 -63.7476079648306 2007 -61.4120621785478 2008 -63.7587564290435 2009 -60.7537281268856 2010 -59.4980317788696 2011 -59.0930120966583 2012 -58.687992414447