Year	Percent change (Units)
1980	37.000
1981	21.488
1982	-53.335
1983	-37.068
1984	38.222
1985	16.564
1986	-12.636
1987	9.585
1988	61.165
1989	18.389
1990	18.726
1991	18.251
1992	22.579
1993	16.596
1994	20.831
1995	-15.242
1996	19.315
1997	24.819
1998	15.478
1999	12.210
2000	21.559
2001	-0.584
2002	1.327
2003	3.022
2004	7.158
2005	5.682
2006	7.946
2007	5.082
2008	4.460
2009	-17.351
2010	19.246
2011	5.595
2012	5.603
2013	3.536
2014	6.447
2015	5.173
2016	2.522
2017	5.538
2018	5.836
2019	-0.720
2020	-10.988
2021	15.512
2022	8.271
2023	5.442
2024	1.851
2025	2.737
2026	2.838
2027	3.063
2028	3.064
2029	3.070