Year	Percent
1990	13.899
1991	14.702
1992	14.826
1993	15.833
1994	16.554
1995	16.103
1996	15.558
1997	14.952
1998	14.365
1999	13.797
2000	13.248
2001	12.718
2002	12.207
2003	11.713
2004	11.236
2005	10.776
2006	10.333
2007	9.907
2008	9.496
2009	9.1
2010	10.1
2011	8.411
2012	6.983
2013	8.36
2014	7.07
2015	6.862
2016	6.605
2017	6.407
2018	6.208
2019	6.01
2020	5.811
2021	5.613
2022	5.414
2023	5.216
2024	5.017
2025	4.819
2026	4.62
2027	4.422
2028	4.223
2029	4.025
2030	3.826