Year	Percent
2002	29.17
2003	33.7
2006	33.26
2007	32.31
2008	30.99
2009	29.59
2010	29.73
2011	28.75
2012	28.96
2013	26.88
2014	25.85
2015	24.63
2016	22.19
2017	20.71
2018	18.94
2019	16.46
2020	16.22