Year	Percent change (Units)
1980	-3.883
1981	-2.474
1982	4.481
1983	14.040
1984	8.925
1985	22.133
1986	11.128
1987	-7.415
1988	-1.417
1989	6.671
1990	-11.590
1991	2.687
1992	-2.202
1993	-3.928
1994	8.014
1995	7.391
1996	1.134
1997	30.177
1998	26.183
1999	-13.083
2000	2.897
2001	-2.534
2002	-7.417
2003	-5.838
2004	-3.571
2005	11.164
2006	8.805
2007	1.097
2008	-7.125
2009	-8.176
2010	-9.513
2011	-0.384
2012	14.363
2013	-4.826
2014	8.225
2015	1.100
2016	1.550
2017	8.578
2018	-0.283
2019	-6.563
2020	-25.273
2021	26.731
2022	-3.229
2023	16.415
2024	3.498
2025	4.229
2026	3.605
2027	2.738
2028	3.135
2029	3.137