Year	Percent
1991	27.424
1992	27.227
1993	27.92
1994	28.033
1995	26.417
1996	27.629
1997	27.32
1998	27.289
1999	27.428
2000	28.271
2001	31.704
2002	32.146
2003	32.719
2004	29.848
2005	30.552
2006	30.787
2007	31.841
2008	33.897
2009	35.426
2010	34.753
2011	22.675
2012	28.456
2013	25.627
2014	26.088
2015	27.86
2016	27.1
2017	26.354
2018	25.244
2019	24.734
2020	24.657
2021	24.524
2022	24.342