Year	Percent change (Units)
1980	1.009
1981	2.961
1982	2.878
1983	-0.124
1984	6.858
1985	1.213
1986	1.810
1987	2.436
1988	0.555
1989	0.428
1990	0.021
1991	-1.322
1992	0.704
1993	5.225
1994	5.583
1995	4.893
1996	4.075
1997	2.447
1998	0.411
1999	4.483
2000	4.216
2001	2.521
2002	4.704
2003	4.427
2004	4.843
2005	3.217
2006	2.813
2007	3.505
2008	-0.357
2009	-1.115
2010	1.715
2011	1.789
2012	2.515
2013	2.319
2014	3.766
2015	3.636
2016	3.945
2017	3.346
2018	3.497
2019	3.079
2020	-1.370
2021	5.628
2022	2.384
2023	0.633
2024	1.047
2025	1.966
2026	2.413
2027	2.378
2028	2.421
2029	2.373