Year	% of internal resources
1975	35.019455252918284
1976	36.10185905750973
1977	37.18426286210117
1978	38.266666666692615
1979	39.349070471284044
1980	40.43212278428015
1981	41.51465629050583
1982	42.59718979680934
1983	43.679723303035026
1984	44.762256809338524
1985	45.84479031564202
1986	46.9273238218677
1987	48.00985732817121
1988	49.09239083439689
1989	50.174924340700386
1990	51.257457846926066
1991	52.33791612622568
1992	53.420319930817115
1993	54.502723735408566
1994	59.545914396887156
1995	64.58910505836576
1996	65.44513618677043
1997	66.3011673151751
1998	67.15719844357977
1999	68.01322957198444
2000	68.8692607003891
2001	69.76478599221791
2002	70.6603112840467
2003	71.55583657587549
2004	72.33463035019454
2005	72.33463035019454
2006	72.33463035019454
2007	72.33463035019454
2008	72.33463035019454
2009	72.33463035019454
2010	72.33463035019454
2011	72.33463035019454
2012	72.33463035019454
2013	72.33463035019454
2014	72.33463035019454
2015	72.33463035019454
2016	72.33463035019454
2017	72.33463035019454
2018	72.33463035019454
2019	72.33463035019454
2020	72.33463035019454