Year	Percent change (Units)
1997	5.732
1998	-0.279
1999	2.841
2000	7.000
2001	3.000
2002	-0.400
2003	0.500
2004	0.600
2005	4.300
2006	4.548
2007	4.944
2008	3.809
2009	-0.025
2010	3.076
2011	3.047
2012	1.803
2013	-1.418
2014	-0.435
2015	-1.298
2016	-0.534
2017	1.217
2018	1.582
2019	0.232
2020	-1.579
2021	6.319
2022	14.811
2023	2.186
2024	2.900
2025	2.137
2026	2.010
2027	1.987
2028	1.988
2029	1.982