Year	Percent change (Units)
1980	3.009
1981	7.671
1982	9.977
1983	5.835
1984	1.575
1985	-1.200
1986	-2.449
1987	-2.105
1988	-0.758
1989	0.701
1990	-0.163
1991	0.296
1992	1.146
1993	3.308
1994	3.561
1995	1.451
1996	2.206
1997	2.035
1998	-0.838
1999	-0.997
2000	-0.952
2001	-0.837
2002	0.589
2003	1.966
2004	2.435
2005	2.326
2006	1.077
2007	4.001
2008	5.122
2009	1.554
2010	0.984
2011	0.190
2012	2.609
2013	3.952
2014	2.490
2015	0.770
2016	2.304
2017	1.347
2018	1.983
2019	1.191
2020	-1.610
2021	-0.409
2022	3.593
2023	-0.297
2024	1.400
2025	1.800
2026	2.102
2027	2.102
2028	2.102
2029	2.102