Year	Percent
1991	97.248
1992	96.973
1993	97.054
1994	97.191
1995	97.135
1996	97.073
1997	97.236
1998	97.389
1999	97.322
2000	97.424
2001	97.451
2002	97.396
2003	97.398
2004	97.515
2005	97.476
2006	97.594
2007	97.595
2008	97.663
2009	97.778
2010	97.532
2011	97.482
2012	97.249
2013	97.125
2014	97.117
2015	97.109
2016	96.999
2017	96.994
2018	96.985
2019	96.975
2020	96.964
2021	96.954
2022	96.943