Year	Percent change (Units)
1980	23.457
1981	20.576
1982	-14.260
1983	-9.882
1984	-4.655
1985	-1.990
1986	-2.659
1987	4.914
1988	-5.888
1989	-1.632
1990	-0.263
1991	-2.787
1992	11.465
1993	-9.185
1994	9.921
1995	0.200
1996	25.067
1997	-4.581
1998	11.376
1999	-11.316
2000	11.597
2001	2.062
2002	-7.953
2003	1.077
2004	4.422
2005	6.578
2006	5.535
2007	6.313
2008	11.212
2009	17.986
2010	19.730
2011	-0.905
2012	18.935
2013	7.036
2014	0.459
2015	-9.219
2016	-7.356
2017	11.877
2018	-4.418
2019	-0.381
2020	64.202
2021	-12.891
2022	-17.773
2023	7.460
2024	66.834
2025	12.157
2026	8.237
2027	-0.369
2028	9.487
2029	7.999