Year	Percent
1991	90.296
1992	90.677
1993	90.598
1994	90.303
1995	90.308
1996	90.436
1997	90.294
1998	90.957
1999	90.99
2000	90.806
2001	91.277
2002	91.418
2003	91.262
2004	90.863
2005	91.083
2006	91.04
2007	90.843
2008	91.047
2009	90.564
2010	90.72
2011	90.384
2012	90.298
2013	89.967
2014	89.777
2015	89.632
2016	89.45
2017	89.36
2018	89.315
2019	89.266
2020	89.218
2021	89.174
2022	89.127