Year	Percent change (Units)
1997	7.161
1998	3.564
1999	19.144
2000	4.026
2001	4.686
2002	5.579
2003	4.785
2004	5.656
2005	8.247
2006	9.161
2007	9.245
2008	9.999
2009	1.728
2010	7.111
2011	8.543
2012	-0.944
2013	-0.512
2014	3.069
2015	4.004
2016	2.135
2017	6.035
2018	2.615
2019	4.853
2020	5.202
2021	9.567
2022	11.898
2023	2.488
2024	2.580
2025	4.207
2026	3.352
2027	3.008
2028	3.000
2029	3.000