Year	Percent change (Units)
1998	47.742
1999	44.429
2000	91.628
2001	46.955
2002	5.462
2003	-53.062
2004	-20.004
2005	5.653
2006	-12.894
2007	16.329
2008	7.394
2009	-15.773
2010	-21.906
2011	14.873
2012	35.760
2013	118.879
2014	2.167
2015	-8.509
2016	-9.139
2017	8.026
2018	66.943
2019	-10.139
2020	-0.380
2021	16.625
2022	35.748
2023	15.604
2024	2.884
2025	13.546
2026	11.466
2027	10.990
2028	7.198
2029	6.594