Year	Percent change (Units)
1980	7.659
1981	34.419
1982	30.918
1983	6.359
1984	34.413
1985	-2.188
1986	3.164
1987	1.559
1988	12.745
1989	2.374
1990	11.402
1991	-4.862
1992	-0.721
1993	-7.852
1994	15.966
1995	9.560
1996	4.626
1997	23.715
1998	-21.548
1999	30.716
2000	8.020
2001	-7.055
2002	2.440
2003	-7.255
2004	8.306
2005	20.152
2006	-0.166
2007	9.367
2008	-5.692
2009	-33.362
2010	12.443
2011	-3.064
2012	20.793
2013	40.436
2014	-0.230
2015	-8.135
2016	-8.949
2017	-6.273
2018	14.068
2019	-10.394
2020	-14.749
2021	33.823
2022	-6.840
2023	-26.468
2024	11.658
2025	30.320
2026	1.816
2027	4.109
2028	2.981
2029	4.121