Year	% of internal resources
1988	14.285714285714285
1989	15.098487394285714
1990	15.911260502857141
1991	16.724033614285712
1992	17.536806722857143
1993	18.34957983142857
1994	19.162352939999998
1995	19.97512605142857
1996	20.78789916
1997	21.600672268571426
1998	22.413445377142857
1999	23.22621848857143
2000	24.038991597142857
2001	24.851764705714285
2002	25.664537814285715
2003	26.47731092571429
2004	27.290084034285716
2005	28.102857142857147
2006	29.77873016
2007	31.454603174285715
2008	33.13047619142857
2009	34.80634920571429
2010	36.48222222285714
2011	38.15809523714285
2012	39.833968254285715
2013	41.50984126857143
2014	43.18571428571429
2015	49.18571428571429
2016	49.92
2017	45.17968571428571
2018	69.47174285714286
2019	73.80879428571428
2020	73.80879428571428