Year	Percent change (Units)
1980	0.700
1981	-5.744
1982	-3.149
1983	3.733
1984	2.000
1985	-6.951
1986	7.146
1987	2.529
1988	-1.957
1989	-7.007
1990	-1.338
1991	10.498
1992	10.299
1993	6.251
1994	5.830
1995	-2.845
1996	5.527
1997	8.111
1998	3.850
1999	-3.385
2000	-0.789
2001	-4.409
2002	-10.894
2003	8.955
2004	8.911
2005	8.852
2006	8.047
2007	9.008
2008	4.057
2009	-5.919
2010	10.125
2011	6.004
2012	-1.026
2013	2.405
2014	-2.513
2015	2.731
2016	-2.080
2017	2.818
2018	-2.617
2019	-2.001
2020	-9.900
2021	10.718
2022	4.956
2023	-1.569
2024	-2.764
2025	5.003
2026	4.495
2027	3.900
2028	3.100
2029	2.301