Year	Percent
1991	26.64
1992	27.001
1993	27.331
1994	27.904
1995	25.643
1996	25.498
1997	26.633
1998	25.623
1999	26.154
2000	25.113
2001	26.611
2002	26.503
2003	26.267
2004	26.565
2005	26.465
2006	26.621
2007	27.43
2008	26.623
2009	24.776
2010	24.146
2011	24.309
2012	23.287
2013	21.534
2014	22.66
2015	25.075
2016	24.195
2017	24.177
2018	24.3
2019	24.389
2020	24.476
2021	24.581
2022	24.624