Year	% of total
1990	84.99324454738468
1991	83.7536780159731
1992	66.1928031985784
1993	31.80301826846704
1994	37.89324849770237
1995	60.025175328178385
1996	37.30286449951722
1997	50.29026372532759
1998	49.50734937812955
1999	42.662235438166874
2000	45.18294729775093
2001	48.56396866840731
2002	28.610255481065412
2003	27.649518269405565
2004	30.36484245439469
2005	28.937786924172865
2006	24.844302306009087
2007	25.24584604950831
2008	26.16984402079723
2009	20.34914477164521
2010	22.153751348020336
2011	32.16689098250337
2012	42.29716276754604
2013	41.15434500648508
2014	42.438709677419354
2015	35.91486087959995