Year	Percent change (Units)
1980	-4.600
1981	11.601
1982	0.813
1983	-2.276
1984	16.469
1985	0.596
1986	2.499
1987	-14.038
1988	32.259
1989	14.139
1990	4.316
1991	-5.232
1992	8.470
1993	5.237
1994	12.447
1995	8.825
1996	7.293
1997	3.166
1998	-0.119
1999	12.257
2000	-0.767
2001	2.273
2002	9.805
2003	8.467
2004	16.904
2005	6.246
2006	-2.378
2007	9.147
2008	3.614
2009	-14.674
2010	10.791
2011	7.042
2012	2.784
2013	6.243
2014	8.074
2015	4.614
2016	3.644
2017	7.111
2018	6.898
2019	2.264
2020	-15.578
2021	14.436
2022	4.729
2023	-0.168
2024	0.139
2025	3.126
2026	3.452
2027	3.617
2028	3.995
2029	3.777