Year	% of total primary
1994	6.84265995025635
1995	9.47867965698242
1997	6.27272987365723
2002	10.5834903717041
2004	9.07443046569824
2005	8.50238037109375
2006	9.42467975616455
2007	10.0862197875977
2008	11.756010055542
2009	13.4035501480103
2010	14.3635501861572
2011	13.1097202301025
2013	16.1832809448242
2015	17.1370391845703
2016	17.8403091430664
2017	19.6071395874023