Year	%
1993	22.4
1997	29.94
1998	26.58
2000	19.01
2003	16.57
2005	18.55
2006	17.29
2007	16.59
2008	18.16
2009	17.87
2010	18.23
2011	17.4
2012	19.02
2013	18.92
2014	19.13
2015	17.11
2016	16.96
2018	17.32
2019	16.94
2020	18.14
2021	18.16