Year	% of internal resources
1987	0.736781916918622
1988	0.8057831068624013
1989	0.8511248434388516
1990	0.8961886639729244
1991	0.9293306172674304
1992	0.9708212796052978
1993	1.0193506453475507
1994	1.0678800110845352
1995	1.115790967299567
1996	1.1637039497929553
1997	1.2092282646274775
1998	1.2593438487045212
1999	1.3056212174233721
2000	1.3518091916507742
2001	1.4020307399075032
2002	1.4404717547776071
2003	1.4622884413255093
2004	1.484105127862877
2005	1.509503702698005
2006	1.5245086894713553
2007	1.5383691230747352
2008	1.5522998964781611
2009	1.5662362386380397
2010	1.5801725807979181
2011	1.5847749434799097
2012	1.5895101637923772
2013	1.5936773738701249
2014	1.5979077937464443
2015	1.6152314199711337
2016	1.6192967920503152
2017	1.6126286755283286
2018	1.6877283980531383
2019	1.697610027180211
2020	1.6976100271802115