Year	Percent
1977	0.25875
1978	0.91948
1979	1.06858
1980	1.92602
1981	1.77298
1982	1.5218
1983	2.89658
1984	0.22645
1985	3.88096
1986	-0.85396
1987	0.9423
1988	0.7393
1989	-0.76961
1990	-1.0118
1991	-0.1166
1992	0.25626
1993	0.03304
1994	-0.08496
1995	0.07562
1996	0.96368
1997	0.72309
1998	2.02684
1999	-0.13837
2000	1.57985
2001	-0.11241
2002	4.34292
2003	2.29666
2004	0.38933
2005	1.35702
2006	0.30517
2007	0.84654
2008	0.07918
2009	2.85682
2010	2.04921
2011	2.22385
2012	1.81207
2013	1.69175
2014	2.07449
2015	2.24417
2016	2.06014
2017	1.93254