Year	Percent
1990	46.163
1991	46.753
1992	47.341
1993	46.751
1994	48.191
1995	47.124
1996	47.644
1997	49.345
1998	49.033
1999	49.013
2000	49.629
2001	52.102
2002	52.617
2003	53.847
2004	53.84
2005	53.201
2006	54.104
2007	55.187
2008	55.565
2009	56.503
2010	57.61
2011	56.817
2012	56.181
2013	56.261
2014	57.812
2015	57.888
2016	58.069
2017	58.078
2018	58.052
2019	57.992
2020	57.89
2021	57.838
2022	57.722
2023	57.568
2024	57.392
2025	57.202
2026	57.087
2027	56.957
2028	56.821
2029	56.682
2030	56.538