Year	% of GDP
1971	1.16035997867584
1972	1.11717998981476
1973	1.42788004875183
1975	1.30332005023956
1979	1.7398099899292
1980	1.84092998504639
1981	1.90917003154755
1982	1.72997999191284
2006	4.68476057052612
2007	4.17489528656006
2008	4.38367223739624
2009	4.81063985824585
2010	3.4794499874115
2011	3.4620099067688
2012	2.60419988632202
2013	3.45445990562439
2014	3.69521999359131
2015	3.2558000087738
2016	4.54397010803223
2017	4.34319019317627
