Year	Percent change (Units)
1980	5.975
1981	10.100
1982	18.100
1983	-0.300
1984	-0.200
1985	-5.300
1986	-3.400
1987	-9.200
1988	3.600
1989	3.000
1990	-10.800
1991	-0.900
1992	6.600
1993	5.700
1994	37.100
1995	16.000
1996	-20.100
1997	0.000
1998	4.085
1999	16.597
2000	-5.826
2001	8.446
2002	21.976
2003	19.339
2004	20.218
2005	-4.501
2006	24.015
2007	37.456
2008	3.091
2009	-10.769
2010	4.051
2011	16.440
2012	-20.961
2013	-2.706
2014	12.312
2015	-22.615
2016	20.453
2017	19.028
2018	4.815
2019	2.269
2020	-9.849
2021	3.476
2022	6.116
2023	13.061
2024	7.338
2025	4.992
2026	5.614
2027	4.700
2028	3.433
2029	4.118