Year	%
1989	10.65
1993	10.39
1995	9.48
1996	7.78
1997	7.26
1998	5.41
1999	5.16
2000	4.99
2001	4.87
2002	4.73
2003	4.88
2004	4.43
2005	4.42
2006	4.17
2007	4.11
2008	4.11
2009	3.98
2010	2.97
2011	2.89
2012	2.76
2013	2.62
2014	2.57
2015	2.5
2016	2.5
2017	2.48
2018	2.48
2019	2.87
2020	2.47
2021	2.48