Year	Percent change (Units)
1980	-9.821
1981	6.186
1982	35.031
1983	-22.330
1984	-18.579
1985	-0.388
1986	-15.253
1987	-11.392
1988	-6.153
1989	4.890
1990	-6.350
1991	3.209
1992	14.060
1993	-4.167
1994	-1.131
1995	23.012
1996	12.520
1997	35.049
1998	1.149
1999	-6.245
2000	-4.193
2001	19.490
2002	11.282
2003	11.327
2004	15.136
2005	63.699
2006	56.372
2007	34.725
2008	7.420
2009	-3.654
2010	-13.072
2011	17.229
2012	16.157
2013	5.798
2014	0.738
2015	-0.098
2016	18.263
2017	-7.630
2018	4.159
2019	-4.349
2020	-23.275
2021	-0.381
2022	18.376
2023	2.283
2024	12.912
2025	1.677
2026	13.186
2027	7.405
2028	4.241
2029	4.165