Year	Percent change (Units)
1980	-6.527
1981	20.164
1982	0.952
1983	14.436
1984	5.387
1985	18.689
1986	14.817
1987	3.833
1988	12.360
1989	1.320
1990	8.100
1991	-3.376
1992	16.149
1993	4.582
1994	4.866
1995	0.774
1996	9.383
1997	10.114
1998	-8.018
1999	7.931
2000	14.599
2001	8.199
2002	1.031
2003	-7.579
2004	-6.657
2005	8.074
2006	0.892
2007	3.699
2008	20.540
2009	-0.803
2010	5.523
2011	4.576
2012	11.973
2013	9.842
2014	1.931
2015	-0.192
2016	-13.248
2017	3.314
2018	6.766
2019	-2.381
2020	7.685
2021	-11.212
2022	17.237
2023	5.310
2024	8.120
2025	3.442
2026	4.223
2027	3.376
2028	3.135
2029	3.415
