Year	Percent change (Units)
1980	5.451
1981	4.375
1982	1.980
1983	3.010
1984	9.577
1985	1.001
1986	-0.149
1987	-2.894
1988	-1.695
1989	1.533
1990	11.697
1991	3.147
1992	2.584
1993	0.736
1994	9.079
1995	1.005
1996	2.328
1997	4.907
1998	1.176
1999	0.337
2000	5.925
2001	-3.398
2002	-5.198
2003	4.288
2004	3.987
2005	5.305
2006	8.461
2007	2.876
2008	5.601
2009	3.037
2010	1.259
2011	3.140
2012	1.010
2013	0.463
2014	3.137
2015	0.367
2016	4.689
2017	6.317
2018	2.900
2019	3.241
2020	-4.992
2021	-1.552
2022	1.915
2023	2.214
2024	2.968
2025	3.516
2026	3.114
2027	2.983
2028	2.493
2029	2.493