Year	Percent
1991	15.372
1992	16.425
1993	15.989
1994	15.357
1995	16.392
1996	15.866
1997	15.085
1998	15.033
1999	16.036
2000	13.799
2001	13.051
2002	13.5
2003	12.767
2004	11.693
2005	12.285
2006	11.836
2007	11.567
2008	10.794
2009	11.31
2010	10.819
2011	10.505
2012	10.517
2013	10.734
2014	10.885
2015	11.103
2016	10.662
2017	10.705
2018	10.632
2019	10.555
2020	10.491
2021	10.428
2022	10.366