Year	% of total
1990	3.4191263282172373
1991	3.417598444336412
1992	3.4313725490196076
1993	3.2051282051282053
1994	3.109444481316785
1995	2.9657451923076925
1996	2.9657451923076925
1997	2.9657451923076925
1998	3.0603804797353185
1999	3.1082785181145836
2000	4.835796387520525
2001	4.473965490914643
2002	4.400584795321637
2003	4.9191606467148254
2004	7.645074224021592
2005	7.769829803728109
2006	7.416950865226727
2007	5.554254488680718
2008	5.423568730020342
