Year	Percent change (Units)
1980	-17.608
1981	26.665
1982	-31.195
1983	0.424
1984	12.478
1985	-12.344
1986	-6.548
1987	-9.518
1988	16.777
1989	3.731
1990	-21.446
1991	-11.343
1992	-11.055
1993	136.802
1994	8.448
1995	9.002
1996	5.381
1997	22.923
1998	7.694
1999	7.901
2000	16.264
2001	-7.309
2002	2.608
2003	9.411
2004	7.104
2005	0.030
2006	0.273
2007	8.840
2008	-18.609
2009	-26.786
2010	95.954
2011	10.456
2012	7.769
2013	10.524
2014	10.405
2015	3.987
2016	4.461
2017	1.769
2018	3.690
2019	1.482
2020	-14.002
2021	10.809
2022	4.953
2023	-9.462
2024	5.566
2025	5.408
2026	4.992
2027	5.739
2028	7.850
2029	6.769