Year	Percent
1977	4.97087
1978	4.49459
1979	3.5776
1980	3.0701
1981	2.95813
1982	2.69925
1983	2.67931
1984	2.03732
1985	2.12785
1986	1.87129
1987	1.90908
1988	1.76773
1989	1.7063
1990	1.78063
1991	1.77993
1992	1.80259
1993	1.74536
1994	1.57654
1995	1.64308
1996	1.61536
1997	1.71902
1998	1.66648
1999	1.66768
2000	1.5969
2001	1.61338
2002	1.73092
2003	1.74807
2004	1.60997
2005	1.75634
2006	1.65212
2007	1.60589
2008	1.54764
2009	1.49164
2010	1.63341
2011	1.63718
2012	1.81263
2013	1.48408
2014	1.4411
2015	1.44541
2016	1.45842
2017	1.66493
2018	1.62679
2019	1.64776
2020	2.2803
2021	2.08179
2022	1.95444