Year	Percent
1981	2.53583
1982	-8.97195
1983	-17.35477
1984	-7.92625
1985	-0.01608
1986	-2.67462
1987	14.81913
1988	8.35234
1989	6.03469
1990	-0.43359
1991	2.2426
1992	-8.45912
1993	4.56296
1994	2.11226
1995	-1.27948
1996	23.02706
1997	7.83481
1998	9.01716
1999	5.07548
2000	-1.03862
2001	9.56123
2002	5.66262
2003	3.38422
2004	4.6473
2005	5.54908
2006	6.66784
2007	4.323
2008	3.79637
2009	3.28988
2010	3.61566
2011	4.03538
2012	4.11875
2013	4.07037
2014	4.37221
2015	3.55604
2016	0.81598
2017	0.77663