Year	Percent
1991	20.806
1992	21.558
1993	21.925
1994	21.384
1995	26.424
1996	24.809
1997	23.388
1998	21.946
1999	23.179
2000	24.564
2001	24.91
2002	25.271
2003	22.906
2004	23.288
2005	27.502
2006	30.138
2007	26.479
2008	27.652
2009	27.278
2010	25.864
2011	26.153
2012	25.904
2013	24.8
2014	23.81
2015	24.158
2016	24.612
2017	24.732
2018	24.949
2019	25.196
2020	25.323
2021	25.477
2022	25.582