Year	Percent
1991	27.829
1992	27.313
1993	29.871
1994	28.558
1995	28.565
1996	27.688
1997	26.778
1998	26.463
1999	24.769
2000	25.413
2001	24.138
2002	23.745
2003	23.676
2004	23
2005	21.47
2006	21.9
2007	23.876
2008	21.958
2009	21.974
2010	20.88
2011	20.875
2012	21.071
2013	20.713
2014	20.105
2015	22.569
2016	23.83
2017	22.77
2018	22.584
2019	22.303
2020	21.992
2021	21.686
2022	21.374
