Year	Percent
1990	80.948
1991	80.841
1992	80.775
1993	80.677
1994	80.579
1995	80.428
1996	80.264
1997	80.173
1998	80.597
1999	80.538
2000	80.397
2001	80.343
2002	80.163
2003	79.997
2004	79.834
2005	79.779
2006	79.563
2007	79.269
2008	78.733
2009	78.642
2010	78.628
2011	79.31
2012	80.027
2013	80.435
2014	80.163
2015	80.405
2016	80.28
2017	80.628
2018	80.96
2019	81.274
2020	81.564
2021	81.814
2022	82.035
2023	82.226
2024	82.385
2025	82.512
2026	82.592
2027	82.637
2028	82.654
2029	82.647
2030	82.621