Year	%
1997	12.22
1998	8.3
1999	8.32
2000	8.1
2001	7.79
2002	8.34
2003	7.56
2004	7.43
2005	7.33
2006	7.33
2007	7.24
2008	7.25
2009	7.15
2010	6.97
2011	6.86
2012	7.02
2013	6.88
2015	6.85
2020	5.15
2021	5.16