Year	% of internal resources
1975	26.279391424619643
1976	27.086445366528356
1977	27.893499308437065
1978	28.700553250345777
1979	29.507607192254497
1980	30.314661134163213
1981	31.121715076071922
1982	31.928769017980635
1983	32.73582295988935
1984	33.54287690179806
1985	34.34993084370678
1986	34.39557399723375
1987	34.441217150760714
1988	34.48686030428769
1989	34.53250345781466
1990	34.57814661134163
1991	35.341628630705394
1992	36.10511065006916
1993	36.86859266943292
1994	37.63207468879668
1995	38.39555670816044
1996	39.159038727524205
1997	39.922510373443984
1998	40.685995850622405
1999	41.44948478561549
2000	42.21296680497925
2001	43.25445988934993
2002	44.29595297372061
2003	45.33744605809129
2004	43.23926002766251
2005	43.49583333333334
2006	43.75240663900415
2007	44.00897994467497
2008	44.26555325034578
2009	44.522126556016595
2010	44.778699861687414
2011	44.778699861687414
2012	44.778699861687414
2013	44.778699861687414
2014	44.778699861687414
2015	44.778699861687414
2016	44.778699861687414
2017	44.778699861687414
2018	44.778699861687414
2019	44.778699861687414
2020	44.778699861687414