Year	Percent
1991	23.906
1992	25.595
1993	26.901
1994	26.258
1995	26.576
1996	25.532
1997	24.399
1998	23.916
1999	24.458
2000	24.486
2001	25.02
2002	24.997
2003	24.044
2004	24.001
2005	23.026
2006	25.456
2007	25.431
2008	25.491
2009	25.432
2010	26.641
2011	25.54
2012	25.578
2013	25.667
2014	26.484
2015	27.76
2016	27.855
2017	27.876
2018	27.959
2019	27.926
2020	27.899
2021	27.876
2022	27.86