Year	% of total primary
1971	93.9408416748047
1972	93.3826370239258
1975	92.433479309082
1981	4.28874015808105
1983	2.85794997215271
1984	2.06353998184204
1985	1.66109001636505
1986	1.24010002613068
1987	0.971430003643036
1988	0.834619998931885
1989	0.657859981060028
1990	0.877390027046204
1991	0.765320003032684
1992	0.726580023765564
1993	1.00155997276306
1999	0
2000	0
2001	1.29732000827789
2002	1.3408499956131
2003	1.63232004642487
2004	1.60135996341705
2005	1.38803994655609
2006	1.17364001274109
2007	1.13700997829437
2008	1.09635996818542
2009	1.10167002677917
2010	1.10688996315002
2011	1.23034000396729
2012	1.23971998691559
2013	1.24260997772217
2014	1.3982800245285
2015	1.65975999832153
2016	1.78541994094849
2017	1.90013003349304
2018	2.04137992858887
2019	2.12163996696472
2020	2.17935991287231