Year	% of GDP
1997	16.044746084166302
1998	16.253127196214084
1999	17.076306878443365
2000	17.02443712519088
2001	16.038740623921505
2002	15.709059410046352
2003	14.663253481592232
2004	14.29554309123741
2005	13.374761619698742
2006	12.583340349357933
2007	11.902944867715478
2008	10.6115120938541
2009	10.061196410183957
2010	10.027154112191381
2011	9.95539617251473
2012	10.020167414165352
2013	9.58849235825594
2014	9.426150823826994
2015	9.975422544339398
2016	9.928004135207868
2017	9.68457578828024
2018	9.866071588318858
2019	9.299638695812476
2020	9.015476513222541