Year	Percent change (Units)
1999	8.432
2000	12.418
2001	12.468
2002	9.928
2003	13.196
2004	15.318
2005	13.567
2006	13.307
2007	12.500
2008	7.558
2009	4.385
2010	5.247
2011	5.471
2012	6.486
2013	7.899
2014	8.200
2015	7.473
2016	6.408
2017	5.750
2018	6.405
2019	6.750
2020	-1.200
2021	-10.486
2022	-3.965
2023	2.546
2024	1.501
2025	2.015
2026	2.019
2027	2.023
2028	2.018
2029	2.013