Year	Percent change (Units)
1980	0.215
1981	2.867
1982	2.841
1983	0.723
1984	2.658
1985	-0.253
1986	1.535
1987	4.051
1988	-0.065
1989	0.736
1990	-3.497
1991	-11.892
1992	-3.064
1993	-0.576
1994	2.947
1995	2.541
1996	0.082
1997	3.143
1998	3.900
1999	3.071
2000	4.479
2001	4.074
2002	4.741
2003	4.074
2004	5.005
2005	4.294
2006	3.946
2007	0.277
2008	1.004
2009	-6.598
2010	1.076
2011	1.867
2012	-1.250
2013	1.803
2014	4.232
2015	3.707
2016	2.201
2017	4.272
2018	5.362
2019	4.864
2020	-4.536
2021	7.086
2022	4.555
2023	-0.908
2024	2.203
2025	3.345
2026	2.800
2027	3.000
2028	3.200
2029	3.200