Year	Percent
1997	94.15186
1998	93.8756
1999	94.12497
2000	93.26057
2001	92.59778
2002	93.39396
2003	93.52376
2004	93.68757
2005	92.53402
2006	92.5037
2007	91.8104
2011	91.86357