Year	Percent change (Units)
1980	-7.821
1981	9.940
1982	-2.262
1983	-63.156
1984	-74.252
1985	528.745
1986	126.560
1987	-5.382
1988	35.066
1989	-19.140
1990	17.853
1991	3.240
1992	19.783
1993	5.865
1994	10.236
1995	-0.223
1996	-5.945
1997	12.983
1998	-4.750
1999	-17.859
2000	7.093
2001	3.033
2002	-12.157
2003	-4.807
2004	18.628
2005	17.375
2006	11.285
2007	14.662
2008	14.818
2009	-1.375
2010	1.781
2011	25.925
2012	3.801
2013	-10.549
2014	-15.895
2015	-11.104
2016	-8.431
2017	2.769
2018	2.481
2019	-1.937
2020	-15.612
2021	26.093
2022	21.459
2023	15.886
2024	-10.820
2025	4.092
2026	3.804
2027	-1.987
2028	4.747
2029	2.329