Year	% of total
1992	8.57806226231538
1993	6.499623703182697
1994	6.983621349258187
1995	4.383005305315718
1996	4.867933058702369
1997	3.948217369222956
1998	3.5693036138222105
1999	3.506205846528623
2000	4.043975675897773
2001	4.116934984520125
2002	4.024078475157509
2003	3.279254500887499
2004	3.777828378489665
2005	3.8583189617629126
2006	3.9006798983023048
2007	4.257252217997465
2008	3.968154589371981
2009	4.643071003847499
2010	4.206757506527415
2011	4.334473768394114
2012	4.919427621529337
2013	5.030658534429418
2014	5.833942699933592
2015	5.450116221806362
2016	5.677274336283186