Year	% of internal resources
1987	0.6189719130895601
1988	0.6578931873043632
1989	0.6968144615209326
1990	0.7357357357357357
1991	0.7746570099505388
1992	0.8135782841671083
1993	0.8524995583819114
1994	0.8914208325967143
1995	0.9303421068132839
1996	0.9685567920862038
1997	0.9742095036212683
1998	0.9798622151563328
1999	0.9855149266913973
2000	0.9911676382264617
2001	0.9968203497615261
2002	1.0024730612965906
2003	1.0081257728316553
2004	1.0137784843667197
2005	1.019431195901784
2006	1.0250839074368487
2007	1.0990990990990992
2008	1.1729553082494257
2009	1.2468799682034977
2010	1.3208046281575694
2011	1.2774355237590531
2012	1.234066419360537
2013	1.190697314962021
2014	1.1485956544780076
2015	1.1280692457163046
2016	1.171347818406642
2017	1.1602190425719838
2018	1.1747041158805864
2019	1.1913089560148382
2020	1.1868927751280691