Year	Percent
1994	-57.36996
1995	-57.24077
1996	-57.24132
1997	-55.74499
1998	-52.88362
1999	-61.15143
2000	-46.60608
2001	-51.95944
2002	-49.37848
2003	-50.43599
2004	-58.68521
2005	-58.99665
2006	-60.02118
2007	-58.44382
2008	-52.15105
2009	-52.41876
2010	-43.72216
2011	-37.49307
2012	-39.2645
2013	-37.93043
2014	-39.60961
2015	-41.02817
2016	-39.07208
2017	-37.06693