Year	Percent change (Units)
1980	12.769
1981	-13.706
1982	-4.753
1983	4.175
1984	1.617
1985	4.584
1986	23.593
1987	6.820
1988	4.317
1989	6.705
1990	0.000
1991	245.354
1992	-6.665
1993	9.521
1994	4.694
1995	-2.248
1996	-25.946
1997	13.257
1998	5.176
1999	-0.123
2000	9.477
2001	6.580
2002	4.955
2003	1.521
2004	-5.105
2005	6.470
2006	2.038
2007	5.069
2008	1.109
2009	12.676
2010	-10.133
2011	-10.968
2012	-0.773
2013	-4.387
2014	8.933
2015	9.404
2016	12.459
2017	23.445
2018	7.470
2019	-6.365
2020	5.213
2021	24.013
2022	-4.319
2023	10.213
2024	13.771
2025	14.716
2026	7.778
2027	0.804
2028	6.274
2029	5.748