Year	% of total
1990	8.475143228252621
1991	8.604219214926832
1992	8.37683836793781
1993	8.478367485980671
1994	8.263580057462203
1995	7.776033009750449
1996	7.781086912029965
1997	8.10103689114344
1998	7.953529604332818
1999	7.8186794563514495
2000	7.956594638418479
2001	7.900802657280465
2002	7.6533630707200535
2003	7.6682807017606
2004	7.553872655973702
2005	7.623458319936948
2006	7.769514861427005
2007	7.838605349398141
2008	8.009816841604259