Year	Percent change (Units)
1980	-10.661
1981	14.805
1982	2.707
1983	6.451
1984	17.286
1985	5.971
1986	-8.582
1987	1.509
1988	14.061
1989	-3.567
1990	21.049
1991	1.605
1992	-6.634
1993	1.411
1994	3.574
1995	-0.964
1996	-1.942
1997	5.508
1998	1.228
1999	10.613
2000	7.571
2001	4.923
2002	65.195
2003	-7.314
2004	8.376
2005	-4.809
2006	1.619
2007	11.808
2008	-3.284
2009	-6.411
2010	24.602
2011	2.354
2012	13.308
2013	10.486
2014	-6.803
2015	6.347
2016	10.655
2017	10.487
2018	3.306
2019	3.352
2020	1.505
2021	11.772
2022	9.371
2023	-2.305
2024	2.329
2025	3.597
2026	4.069
2027	3.549
2028	3.002
2029	3.927