Year	Percent change (Units)
1980	0.000
1981	0.000
1984	0.000
1986	0.000
1989	2.584
1990	-2.965
1991	2.348
1992	33.524
1993	9.139
1994	4.602
1995	6.507
1996	16.879
1997	28.135
1998	-4.455
1999	-10.354
2000	21.248
2001	18.570
2002	12.092
2003	-15.828
2004	-2.105
2005	10.500
2006	19.237
2007	11.060
2008	4.038
2009	-5.547
2010	3.347
2011	8.566
2012	-2.285
2013	-8.700
2014	-3.453
2015	16.738
2016	9.486
2017	5.496
2018	0.315
2019	-0.381
2020	-21.307
2021	16.055
2022	-6.126
2023	6.217
2024	11.031
2025	3.602
2026	3.811
2027	6.324
2028	4.512
2029	4.031