Year	Percent change (Units)
1980	-5.344
1981	-3.945
1982	5.454
1983	8.813
1984	11.235
1985	3.132
1986	7.427
1987	7.788
1988	13.337
1989	8.174
1990	0.104
1991	-5.255
1992	6.594
1993	3.792
1994	4.425
1995	6.178
1996	9.469
1997	9.229
1998	7.467
1999	6.898
2000	10.296
2001	7.331
2002	4.831
2003	0.951
2004	6.622
2005	7.860
2006	12.941
2007	-2.648
2008	-0.962
2009	-7.774
2010	10.521
2011	3.490
2012	2.220
2013	3.259
2014	4.123
2015	3.503
2016	3.933
2017	2.432
2018	0.557
2019	2.586
2020	-12.410
2021	5.789
2022	9.239
2023	-8.393
2024	-0.136
2025	-0.372
2026	0.791
2027	1.431
2028	1.502
2029	1.156