Year	Percent
1990	45.802
1991	45.805
1992	45.724
1993	45.588
1994	45.447
1995	45.315
1996	45.304
1997	45.324
1998	45.351
1999	45.371
2000	45.404
2001	45.497
2002	45.613
2003	45.725
2004	45.796
2005	45.749
2006	45.657
2007	45.532
2008	45.403
2009	45.173
2010	45.03
2011	44.896
2012	44.718
2013	44.6
2014	44.466
2015	44.397
2016	44.136
2017	44.263
2018	44.423
2019	44.576
2020	44.693
2021	44.788
2022	44.841
2023	44.861
2024	44.873
2025	44.891
2026	44.923
2027	44.956
2028	44.979
2029	44.97
2030	44.918