Year	% of internal resources
1970	3.4799999999999995
1971	3.634
1972	3.788
1973	3.9419999999999997
1974	4.096
1975	4.25
1976	4.194
1977	4.138
1978	4.082
1979	4.026
1980	3.9699999999999998
1981	4.516
1982	5.061999999999999
1983	5.608
1984	6.154
1985	6.7
1986	6.6000000000000005
1987	6.5
1988	6.4
1989	6.3
1990	6.2
1991	6.1
1992	6
1993	5.8999999999999995
1994	5.800000000000001
1995	5.7
1996	5.795
1997	5.89
1998	5.985
1999	6.08
2000	5.942
2001	5.804
2002	5.666
2003	5.5280000000000005
2004	5.390000000000001
2005	5.252
2006	5.114
2007	4.976
2008	4.838
2009	4.7
2010	4.760000000000001
2011	4.63
2012	4.46
2013	4.31
2014	4.6
2015	4.4799999999999995
2016	4.44
2017	4.5600000000000005
2018	5.220000000000001
2019	4.93
2020	4.78