Year	Percent
1981	98.80252
1982	98.22386
1983	98.8947
1984	102.14557
1985	103.30968
1986	103.29576
1987	100.9834
1988	104.63978
1989	102.20605
1990	99.72859
1993	100.73247
1994	101.8171
2004	102.18254
2006	96.60474
2007	98.18195
2008	99.86369
2009	102.23044
2010	103.18162
2011	102.08683
2012	102.08788
2013	99.3103
2014	97.59393
2015	98.9223
2016	97.17855