Year	% of internal resources
1991	43.24485981308411
1992	46.680829252336444
1993	46.298634560747665
1994	45.98123646728972
1995	45.63634219626168
1996	44.64033241121495
1997	44.28293723364486
1998	42.81003342990655
1999	42.4024335046729
2000	41.95072755140187
2001	41.02730214018692
2002	39.97985392831775
2003	38.93240571654206
2004	37.8849575046729
2005	35.30492494084112
2006	32.72489237691589
2007	30.149532710280376
2008	30.37414330214953
2009	30.603426791308408
2010	30.831775700934582
2011	28.44485981308411
2012	26.056697819345796
2013	23.669158878504675
2014	23.39408099691589
2015	23.119003115233646
2016	22.84392523364486
2017	22.84392523364486
2018	22.84392523364486
2019	22.84392523364486
2020	22.84392523364486