Year	Percent
1990	18.498
1991	19.361
1992	19.11
1993	18.86
1994	17.1
1995	16.12
1996	15.32
1997	15.44
1998	14.98
1999	12.95
2000	12.53
2001	11.48
2002	9.33
2003	8.2
2004	8.13
2005	8.92
2006	8.14
2007	7.62
2008	7.59
2009	7.47
2010	7.73
2011	7.83
2012	7.66
2013	7.49
2014	7.9
2015	7.91
2016	8.39
2017	8.242
2018	8.094
2019	7.946
2020	7.798
2021	7.65
2022	7.502
2023	7.354
2024	7.206
2025	7.058
2026	6.91
2027	6.762
2028	6.614
2029	6.466
2030	6.318