Year	Percent
1975	93.86408
1976	119.77276
1977	127.98304
1978	114.28441
1979	113.77549
1980	80.48976
1981	82.77859
1982	81.83426
1983	79.70879
1984	85.02144
1985	70.89333
1986	55.74727
1987	55.3874
1988	59.92345
1989	67.4704
1990	62.93897
1991	61.9043
1992	62.20929
1993	51.59104
1994	53.66495
1995	50.0571
1996	54.24449
1997	51.12411
1998	45.83954
1999	43.47844
2000	47.10646
2001	46.35998
2002	42.42456
2003	36.96946
2004	37.01633
2005	41.60086
2006	40.48823
2007	41.56877
2008	44.09779
2009	35.04783
2010	39.00731
2011	38.26691
2012	36.08171
2013	34.59959
2014	47.70972
2015	52.43634
2016	53.59113
2017	56.4198