Year	Percent change (Units)
1980	-16.650
1981	2.056
1982	-0.209
1983	-2.029
1984	11.725
1985	1.697
1986	5.721
1987	7.705
1988	18.796
1989	9.016
1990	5.282
1991	2.303
1992	16.747
1993	2.850
1994	12.961
1995	14.180
1996	12.513
1997	0.914
1998	-7.563
1999	5.658
2000	14.778
2001	1.410
2002	0.046
2003	7.121
2004	8.360
2005	7.811
2006	6.027
2007	1.446
2008	1.439
2009	-17.077
2010	13.488
2011	7.180
2012	4.835
2013	3.339
2014	6.495
2015	0.440
2016	-1.175
2017	3.307
2018	3.814
2019	0.988
2020	-6.751
2021	5.142
2022	7.871
2023	-1.335
2024	2.188
2025	2.038
2026	1.703
2027	1.644
2028	1.425
2029	1.325