Year	Percent change (Units)
1980	-2.734
1981	-26.079
1982	-20.240
1983	13.451
1984	9.307
1985	6.562
1986	17.585
1987	17.582
1988	-0.908
1989	16.913
1990	10.439
1991	-4.394
1992	23.594
1993	14.525
1994	5.132
1995	2.976
1996	2.983
1997	14.014
1998	24.824
1999	0.461
2000	-2.356
2001	0.010
2002	6.130
2003	4.544
2004	4.812
2005	6.946
2006	7.816
2007	10.088
2008	6.659
2009	-18.736
2010	18.726
2011	10.671
2012	7.825
2013	1.681
2014	5.046
2015	4.498
2016	8.938
2017	5.013
2018	2.856
2019	-2.297
2020	-12.929
2021	19.246
2022	6.022
2023	5.612
2024	8.599
2025	7.345
2026	6.696
2027	6.418
2028	6.275
2029	6.239