Year	Percent change (Units)
1980	0.328
1981	14.517
1982	-2.559
1983	4.559
1984	7.967
1985	2.703
1986	5.340
1987	4.234
1988	7.384
1989	8.823
1990	3.509
1991	0.394
1992	4.844
1993	8.517
1994	12.336
1995	13.777
1996	2.492
1997	3.772
1998	2.541
1999	0.009
2000	12.421
2001	2.755
2002	-2.562
2003	-0.704
2004	6.418
2005	3.320
2006	8.330
2007	7.123
2008	-1.593
2009	-18.902
2010	12.421
2011	6.386
2012	1.363
2013	0.653
2014	2.868
2015	4.533
2016	1.510
2017	4.923
2018	1.845
2019	1.077
2020	-9.167
2021	13.920
2022	6.550
2023	-1.475
2024	0.540
2025	1.468
2026	1.486
2027	1.656
2028	1.555
2029	1.843