Year	% of total
2000	14.368678669664355
2001	13.804333166734098
2002	14.28510481682367
2003	15.082631526317458
2004	16.11641133466509
2005	14.025736078853518
2006	13.718254573192167
2007	14.267572155101545
2008	15.302664159399734
2009	17.323699637549712
2010	21.10587692594879
2011	24.19286423214056
2012	29.68773614415909
2013	26.731118212466924
2014	24.060368154274173