Year	% of GDP
1972	15.7531536952256
1973	14.9947883974575
1974	16.7370783045593
1975	20.6387214451135
1976	16.0355626478842
1977	17.9572502767255
1978	18.2350871455136
1980	21.7604995302545
1981	20.6931206409182
1982	20.6496687969178
1983	21.5719213063941
1984	15.9105858934833
1985	12.5604363130221
1986	13.0766464056549
1987	13.8427040675841
1988	14.8426766368612
1989	17.3906795008666
1990	17.7235835753878
1991	16.2154820750779
1992	16.7343046067541
1993	19.3515307669196
1994	19.761750619635
1995	18.3119083334252
1996	19.6526394594281
1997	20.2969988993478
1998	19.5789022222374
1999	16.6075643998621
2000	15.9215884088608
2001	17.0180747029885
2002	17.2623887952709
2003	17.8725963947703
2004	17.7823187975686
2005	17.8466126607813
2006	17.536300573711
2007	16.7213436237158
2008	16.5055504302905
2009	15.5387328994146
2010	17.1730350469211
2011	16.7736851452122
2012	17.4029023336275
2013	18.1750570139632
2014	18.4014529528394
2015	19.2756249140402
2016	21.4801635554381
2017	21.7019917885127
2018	22.9700687581335