Year	% of internal resources
1993	46.624872430383434
1994	43.49030470914128
1995	36.90042280215775
1996	33.197259075667006
1997	26.971861787432573
1998	29.071293191427323
1999	28.663070418428344
2000	27.278028867181803
2001	25.16401807843709
2002	25.251494386936873
2003	28.80886426592798
2004	36.492200029158774
2005	40.399475142149
2006	41.21592068814696
2007	43.91310686689022
2008	41.88657238664529
2009	35.92360402391019
2010	30.99577197842251
2011	35.54454002041114
2012	42.877970549642804
2013	43.082081936142295
2014	41.69704038489576
2015	47.70374690188074
2016	46.39160227438402
2017	41.76993730864558
2018	39.56845021140108
2019	41.76993730864558
2020	41.25965884239685