Year	Percent
1980	-0.30614
1981	-0.06699
1982	-6.00803
1983	0.41501
1984	-0.12785
1985	0.9516
1986	3.80544
1987	3.61013
1988	0.7117
1989	2.32147
1990	2.60357
1991	2.65883
1992	2.31698
1993	2.14069
1994	2.45666
1995	1.81226
1996	2.0683
1997	2.24486
1998	2.13258
1999	2.09121
2000	3.57378
2001	2.36055
2002	2.7556
2003	3.02004
2004	4.31467
2005	4.555
2006	4.05198
2007	7.08806
2008	7.97903
2009	6.73534
2010	8.36376
2011	15.26593
2012	7.89894
2013	10.95038
2014	9.01659
2015	7.43726
2016	10.81374
2017	11.25686