Year	Percent
2006	36.9
2007	38.8
2008	34.9
2009	34.9
2010	37.3
2011	34.1
2012	30
2013	26.2
2014	23.5
2015	21.6
2016	22
2017	21.9
2018	20.1
2019	19.5
2020	21.3
2021	17.5
2022	15.6