Year	Percent change (Units)
1980	3.792
1981	-2.765
1982	9.619
1983	-0.557
1984	4.337
1985	6.324
1986	8.300
1987	-2.544
1988	10.415
1989	2.366
1990	4.035
1991	7.547
1992	-2.908
1993	-1.003
1994	11.494
1995	-6.328
1996	13.460
1997	-2.012
1998	7.979
1999	0.529
2000	1.593
2001	7.552
2002	3.316
2003	6.317
2004	4.802
2005	2.978
2006	7.760
2007	2.706
2008	5.923
2009	4.244
2010	3.816
2011	5.246
2012	3.010
2013	4.535
2014	2.669
2015	4.345
2016	0.521
2017	5.058
2018	3.066
2019	2.891
2020	-7.178
2021	8.021
2022	1.259
2023	3.017
2024	3.145
2025	3.302
2026	3.382
2027	3.395
2028	3.379
2029	3.409