Year	% of total
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0.9158815987513238
1985	1.745644923121405
1986	0.07124198527665639
1987	0.47853008149273846
1988	0.28286042605851675
1989	0.8260993215151474
1990	1.003944870546313
1991	0.6152480832163566
1992	0.727665348402363
1993	0.17541353144743943
1994	0.021150510880976463
1995	0.9140024891056274
1996	0.8332246170325257
1997	1.0289562377022035
1998	1.0147693225754317
1999	1.1881714647641584
2000	1.732825083832507
2001	4.346621695666468
2002	4.002649918564184
2003	3.6663656649439123
2004	2.9967505736179616
2005	2.445209201231661
2006	3.2799395235812727
2007	2.774364423437651
2008	3.016626103781958
2009	2.7797503223411946
2010	2.815926475293023
2011	2.94476612437636
2012	2.902154086684617
2013	2.7053244988583356
2014	2.603567927591759