Year	Percent change (Units)
1980	13.355
1981	10.338
1982	7.437
1983	4.566
1984	0.094
1985	7.484
1986	3.415
1987	2.058
1988	10.737
1989	1.901
1990	5.637
1991	-18.192
1992	26.220
1993	0.819
1994	27.351
1995	17.507
1996	6.857
1997	13.876
1998	4.603
1999	6.551
2000	2.189
2001	-0.893
2002	12.442
2003	8.525
2004	35.837
2005	16.645
2006	11.499
2007	18.801
2008	3.673
2009	7.250
2010	15.996
2011	10.433
2012	1.534
2013	-3.441
2014	6.108
2015	1.176
2016	4.521
2017	13.372
2018	3.942
2019	-3.742
2020	-13.712
2021	19.380
2022	10.040
2023	-0.093
2024	4.860
2025	6.271
2026	6.124
2027	6.130
2028	6.135
2029	5.852