Year	% of revenue
1995	16.12140323216397
1996	14.644970414201183
1997	10.770617395223073
1998	14.968197879858657
1999	13.2655269422203
2000	16.51658497663285
2001	15.10442495296429
2002	15.446188481020574
2003	17.585281111813014
2004	17.94494266720207
2005	15.825214053734868
2006	14.08521724514665
2007	14.906486107097146
