Year	Percent change (Units)
1980	21.613
1981	7.345
1982	-14.984
1983	-2.497
1984	7.710
1985	-3.393
1986	22.199
1987	2.322
1988	-8.666
1989	11.141
1990	-7.213
1991	5.749
1992	11.626
1993	-6.856
1994	4.574
1995	6.563
1996	0.862
1997	10.660
1998	2.600
1999	9.432
2000	14.204
2001	0.953
2002	-6.969
2003	-2.060
2004	11.028
2005	8.317
2006	11.158
2007	11.612
2008	0.016
2009	-13.302
2010	7.723
2011	5.817
2012	8.552
2013	1.056
2014	2.532
2015	8.096
2016	5.310
2017	5.803
2018	9.734
2019	-0.080
2020	0.458
2021	12.485
2022	6.063
2023	0.333
2024	1.155
2025	2.713
2026	2.852
2027	2.337
2028	2.386
2029	2.235