Year	Percent
1990	16.141
1991	16.179
1992	16.105
1993	17.139
1994	16.771
1995	16.842
1996	16.5
1997	17.5
1998	12.27
1999	13.87
2000	10.24
2001	10.14
2002	12.83
2003	11.03
2004	15.15
2005	15.04
2006	16.82
2007	17.67
2008	19.33
2009	12.48
2010	8.23
2011	7.7
2012	9.41
2013	10.68
2014	9.48
2015	10.49
2016	10.46
2017	10.179
2018	9.899
2019	9.618
2020	9.338
2021	9.057
2022	8.776
2023	8.496
2024	8.215
2025	7.935
2026	7.654
2027	7.373
2028	7.093
2029	6.812
2030	6.532