Year	%
1988	18.6
1991	16.4
1993	13.01
1996	10.92
1997	8.88
1998	14.09
1999	10.38
2000	9.53
2001	8.01
2002	7.51
2003	7.94
2004	12.06
2005	7.55
2006	6.96
2007	6.99
2008	6.79
2009	6.7
2010	5.82
2011	6.61
2012	6.6
2013	6.98
2014	3.37
2016	6.22
2020	5.65
2021	5.61