Year	Percent change (Units)
2000	12.997
2001	-39.136
2002	21.730
2003	59.377
2004	-8.314
2005	9.057
2006	-44.646
2007	25.869
2008	-12.982
2009	-38.558
2010	-5.561
2011	89.488
2012	-13.311
2013	-6.101
2014	33.695
2015	1.013
2016	20.766
2017	-36.439
2018	-29.358
2019	-0.312
2020	34.948