Year	Percent change (Units)
1980	-3.212
1981	-1.086
1982	-21.257
1983	-16.601
1984	6.406
1985	-6.020
1986	-9.253
1987	23.846
1988	3.780
1989	5.591
1990	-8.069
1991	10.378
1992	37.625
1993	8.416
1994	5.806
1995	6.615
1996	-6.386
1997	27.334
1998	29.822
1999	1.046
2000	8.647
2001	11.206
2002	6.366
2003	-0.577
2004	7.878
2005	-0.602
2006	6.447
2007	7.827
2008	-5.729
2009	-7.706
2010	10.004
2011	6.970
2012	2.777
2013	4.566
2014	3.370
2015	3.648
2016	0.942
2017	2.825
2018	3.927
2019	4.857
2020	-5.757
2021	19.486
2022	4.361
2023	5.162
2024	5.600
2025	5.920
2026	5.936
2027	6.016
2028	5.790
2029	5.850