Year	Percent change (Units)
1980	1.278
1981	2.702
1982	6.112
1983	-2.058
1984	9.651
1985	6.437
1986	8.842
1987	8.268
1988	10.353
1989	6.013
1990	5.454
1991	2.270
1992	3.077
1993	5.418
1994	5.404
1995	3.462
1996	5.897
1997	7.327
1998	1.024
1999	3.943
2000	9.714
2001	5.309
2002	1.370
2003	-3.936
2004	3.996
2005	9.734
2006	3.150
2007	0.601
2008	11.179
2009	-3.379
2010	0.044
2011	1.617
2012	-0.517
2013	5.706
2014	7.587
2015	0.717
2016	3.910
2017	0.017
2018	2.053
2019	4.050
2020	-14.561
2021	-0.891
2022	8.823
2023	3.450
2024	4.731
2025	4.255
2026	3.800
2027	3.050
2028	2.850
2029	2.851