Year	Percent change (Units)
1985	-3.672
1986	-0.602
1987	8.623
1988	31.520
1989	-39.016
1990	-0.963
1991	42.566
1992	22.435
1993	-9.427
1994	-22.300
1995	25.269
1996	-14.667
1997	24.849
1998	11.469
1999	-9.331
2000	12.399
2001	14.108
2002	-25.217
2003	-20.884
2004	57.667
2005	35.160
2006	34.752
2007	33.006
2008	1.362
2009	-19.557
2010	-2.891
2011	15.393
2012	24.396
2013	-9.687
2014	-18.532
2015	-23.102
2016	-50.061
2017	-34.651
2018	0.300
2019	-22.200
2020	-27.062
2021	-2.196
2022	10.953
2023	4.930
2024	7.702
2025	6.483