Year	% of total
1990	9.822446429359795
1991	10.142720967815482
1992	10.465162965447245
1993	10.668454750354453
1994	9.052392559032059
1995	8.978004292079566
1996	8.873659493232603
1997	8.722762078988698
1998	8.191704526973414
1999	7.886501107474159
2000	7.508299620430936
2001	7.642164248788583
2002	7.391849761428673
2003	7.529529257859612
2004	7.585601028922691
2005	7.482730400234815
2006	7.823648864930456
2007	7.773843112348628
2008	7.88304033510911