Year	Percent change (Units)
1980	-24.638
1981	-15.819
1982	1.714
1983	-0.899
1984	7.224
1985	2.471
1986	-5.904
1987	-5.975
1988	5.162
1989	25.187
1990	19.512
1991	-1.114
1992	2.553
1993	12.541
1994	4.489
1995	6.231
1996	2.430
1997	3.378
1998	-6.227
1999	-5.300
2000	-10.458
2001	-5.042
2002	-11.611
2003	8.525
2004	0.022
2005	-1.359
2006	-10.103
2007	3.139
2008	-3.008
2009	10.331
2010	11.095
2011	-14.358
2012	-12.828
2013	2.112
2014	-4.086
2015	22.797
2016	-4.441
2017	-3.808
2018	-2.999
2019	15.543
2020	4.606
2021	2.395
2022	-2.786
2023	-3.228
2024	3.502
2025	1.699
2026	2.292
2027	2.320
2028	1.645
2029	1.316