Year	% of total
1990	55.703205637571955
1991	56.26929980773175
1992	55.644932257325095
1993	55.639002281359865
1994	55.54366447999831
1995	56.519435118666486
1996	56.06162004841302
1997	56.5373043014048
1998	57.629162640934496
1999	57.85860967962329
2000	58.13931049101486
2001	56.61639931685323
2002	57.53117627813981
2003	57.68530374150351
2004	56.378690244203916
2005	56.90436452830233
2006	55.61575631964472
2007	55.917935701296166
2008	55.423830370973185