Year	Percent change (Units)
1980	4.437
1981	-6.807
1982	5.216
1983	-1.425
1984	-1.322
1985	9.847
1986	19.899
1987	27.959
1988	16.384
1989	17.804
1990	9.043
1991	11.537
1992	5.903
1993	-7.115
1994	15.485
1995	13.227
1996	8.086
1997	13.429
1998	14.618
1999	13.200
2000	10.268
2001	3.289
2002	4.107
2003	6.769
2004	10.562
2005	6.758
2006	7.869
2007	9.287
2008	-6.029
2009	-19.256
2010	8.195
2011	-0.502
2012	-5.728
2013	0.611
2014	6.597
2015	5.075
2016	1.718
2017	7.012
2018	2.747
2019	-0.067
2020	-11.220
2021	15.011
2022	5.405
2023	-0.287
2024	1.862
2025	4.067
2026	3.207
2027	3.409
2028	3.129
2029	3.180