Year	% of total
1960	1.0978956999085088
1961	1.8945634266886324
1962	6.740702479338843
1963	4.80901978831109
1964	10.309064509437876
1965	8.276157804459691
1966	1.3796810607418024
1967	1.6818028927009756
1968	7.941082292667308
1969	2.2753792298716453
1970	4.934122075826835
1971	3.558763931104356
1972	2.48868778280543
1973	3.9419934640522873
1974	3.2007487131492747
1975	2.775441547518924
1976	2.946446346804698
1977	1.4664246823956444
1978	1.5959997260086307
1979	2.271175923053056
1980	2.2951466526371167
1981	2.416087962962963
1982	1.6148987432441233
1983	1.2684872320389962
1984	0.6303724928366762
1985	5.135566188197767
1986	16.401830078221085
1987	25.75237526737303
1988	26.90454950936664
1989	28.72519472386395
1990	32.121939171547524
1991	33.0025565123789
1992	34.621746615805286
1993	36.97321716682801
1994	37.17048573434607
1995	40.5986000482742
1996	36.58947613098178
1997	38.20754716981132
1998	30.984141671164572
1999	35.2588898727688
2000	33.86516646684497
2001	29.50528504591925
2002	33.32311062431545
2003	31.226757808301624
2004	33.14520266803489
2005	32.96527236511648
2006	30.79298418972332
2007	26.437222790856364
2008	24.62012094557449
2009	26.06200234428681
2010	13.223817772066083
2011	18.979340117175454
2012	28.714674390029842
2013	23.425812324375666
2014	23.002752169980177
2015	28.71823872389384