Year	% of internal resources
1980	2.183673469387755
1981	2.199125364489796
1982	2.214577259387755
1983	2.230029154489796
1984	2.2454810495918367
1985	2.2609329446938773
1986	2.2763848395918367
1987	2.2918367346938773
1988	2.3072886297959183
1989	2.3227405246938777
1990	2.3381924197959183
1991	2.353644314897959
1992	2.36909621
1993	2.3845481048979593
1994	2.4
1995	2.3300556585714287
1996	2.2601113173469387
1997	2.190166975918367
1998	2.1202226344897963
1999	2.050278293061224
2000	1.9803339518367349
2001	1.9103896104081635
2002	1.8404452689795916
2003	1.7705009275510202
2004	1.7005565863265306
2005	1.6306122448979592
2006	1.560204081632653
2007	1.489795918367347
2008	1.5173469387755103
2009	1.5448979591836733
2010	1.6968253967346938
2011	1.8487528344897957
2012	2.0006802720408166
2013	2.152607709795918
2014	2.3045351473469387
2015	2.4564625851020407
2016	2.608390022653061
2017	2.7603174604081633
2018	2.9122448979591837
2019	3.1340816326530616
2020	3.144489795918367