Year	Percent change (Units)
1980	-3.557
1981	-2.851
1982	4.532
1983	6.167
1984	9.457
1985	2.342
1986	6.664
1987	7.775
1988	12.357
1989	7.117
1990	0.406
1991	-4.508
1992	6.547
1993	3.115
1994	5.738
1995	5.328
1996	9.198
1997	9.836
1998	7.460
1999	7.397
2000	9.434
2001	6.180
2002	4.719
2003	1.647
2004	6.714
2005	7.029
2006	10.563
2007	-1.375
2008	-1.009
2009	-7.024
2010	8.964
2011	2.928
2012	2.454
2013	3.243
2014	5.095
2015	4.956
2016	3.977
2017	3.165
2018	3.098
2019	2.718
2020	-16.003
2021	6.142
2022	14.608
2023	-1.635
2024	-0.740
2025	-0.175
2026	0.803
2027	1.453
2028	1.525
2029	1.173