Year	Percent change
1980	-15.614
1981	0.225
1982	45.337
1983	21.728
1984	10.149
1985	25.437
1986	19.391
1987	3.084
1988	-27.444
1989	29.674
1990	36.49
1991	71.417
1992	35.017
1993	19.604
1994	38.545
1995	22.229
1996	28.66
1997	15.616
1998	-2.77
1999	7.933
2000	-5.97
2001	6.276
2002	9.529
2003	9.036
2004	15.745
2005	5.95
2006	14.301
2007	13.309
2008	2.128
2009	3.74
2010	6.577
2011	4.297
2012	15.594
2013	16.938
2014	10.977
2015	9.768
2016	10.723
2017	16.388
2018	12.804
2019	12.852
2020	12.471
2021	12.375
2022	12.383
2023	12.255
2024	12.306