Year	Percent
1976	7.85275
1977	9.06377
1978	14.03163
1979	8.47429
1980	14.10279
1981	20.20255
1982	24.35349
1983	21.08061
1984	14.56774
1985	10.5484
1986	16.83918
1987	13.00494
1988	8.65591
1989	8.88711
1990	11.01381
1991	8.34962
1992	4.87519
1993	2.68308
1994	1.3124
1995	2.3047
1996	1.86295
1997	3.41779
1998	3.75948
1999	3.60527
2000	1.71259
2001	2.22491
2002	2.23398
2003	-1.05422
2004	2.04391
2005	2.33875
2006	1.06426
2007	3.26797
2008	4.292
2009	7.19185
2010	4.59487
2011	6.73218
2012	6.21042
2013	5.50718
2014	1.78855
2015	3.73363
2016	1.94633
2017	0.60382
2018	2.48899
2019	0.79192
2020	16.12097
2021	12.89859