Year	Percent change (Units)
1980	2.622
1981	-1.397
1982	3.562
1983	-2.699
1984	3.402
1985	4.744
1986	6.665
1987	7.672
1988	8.444
1989	8.068
1990	5.042
1991	2.956
1992	1.767
1993	-3.319
1994	8.863
1995	7.523
1996	2.446
1997	7.976
1998	11.900
1999	6.951
2000	15.353
2001	2.382
2002	1.946
2003	0.894
2004	6.204
2005	6.320
2006	5.601
2007	5.756
2008	1.295
2009	-9.355
2010	8.893
2011	5.837
2012	0.200
2013	2.418
2014	4.899
2015	5.898
2016	2.929
2017	4.487
2018	3.079
2019	2.344
2020	-12.324
2021	9.049
2022	8.796
2023	-0.087
2024	0.970
2025	2.365
2026	2.492
2027	2.682
2028	2.815
2029	2.634