Year	% of GDP
1987	13.0983252945342
1988	13.9944028135004
1989	14.319282525772
1990	14.8279156737099
1991	15.0278599902133
1992	15.5105249576913
1993	15.2783731372324
1994	15.3005544460065
1995	15.7140785937578
1996	16.7271137107534
1997	17.4870582665368
1998	15.3958109880207
1999	15.06574808836
2000	14.5472220259458
2001	15.5557629654801
2002	14.1283997552328
2003	14.1603779271476
2004	15.5941117446526
2005	16.118129435075
2006	16.4238860146651
2007	17.3951702551334
2008	17.4106059656344
2009	16.7419671545871
2010	16.2939942517951
2011	16.8542735255039
2012	17.2319912927405
2013	16.1416693776447
2014	15.8727174148127
2015	16.1354884906271