Year	Percent change (Units)
1980	0.328
1981	14.517
1982	6.739
1983	10.579
1984	13.985
1985	0.994
1986	-5.220
1987	6.622
1988	5.627
1989	5.830
1990	10.437
1991	11.318
1992	7.057
1993	10.362
1994	20.272
1995	9.519
1996	10.690
1997	16.415
1998	6.729
1999	6.217
2000	10.126
2001	3.388
2002	2.879
2003	4.835
2004	5.846
2005	0.088
2006	3.475
2007	10.080
2008	-0.978
2009	-11.429
2010	11.753
2011	8.773
2012	0.926
2013	6.291
2014	3.843
2015	3.910
2016	4.235
2017	5.073
2018	1.402
2019	0.797
2020	-8.594
2021	9.343
2022	4.523
2023	-1.552
2024	3.685
2025	3.861
2026	2.763
2027	2.641
2028	2.539
2029	2.539