Year	Percent change (Units)
1980	6.724
1981	9.700
1982	5.834
1983	3.704
1984	3.904
1985	2.587
1986	0.350
1987	0.737
1988	0.290
1989	2.557
1990	3.043
1991	4.328
1992	4.778
1993	3.547
1994	3.687
1995	3.468
1996	3.479
1997	2.655
1998	5.293
1999	2.731
2000	1.551
2001	1.427
2002	1.793
2003	1.074
2004	1.420
2005	3.039
2006	3.621
2007	2.027
2008	5.429
2009	0.597
2010	1.720
2011	3.174
2012	1.664
2013	2.105
2014	3.143
2015	2.104
2016	2.076
2017	3.799
2018	0.969
2019	0.663
2020	-1.139
2021	2.477
2022	3.379
2023	2.489
2024	2.793
2025	2.514
2026	2.172
2027	2.048
2028	2.039
2029	2.059