Year	Percent
1978-01-01	7.2011000000000000
1979-01-01	5.6430600000000000
1980-01-01	5.3777500000000000
1981-01-01	5.3777500000000000
1982-01-01	7.2033500000000000
1983-01-01	7.3873800000000000
1984-01-01	7.4239999999999995
1985-01-01	7.7378899999999990
1986-01-01	7.8332399999999990
1987-01-01	7.1279999999999990
1988-01-01	5.7477400000000000
1989-01-01	4.9279900000000000
1990-01-01	4.3154699999999995
1991-01-01	3.7995099999999997
1992-01-01	3.3783700000000000
1993-01-01	3.4677200000000000
1994-01-01	3.7366300000000003
1995-01-01	3.7295000000000000
1996-01-01	3.9301100000000000
1997-01-01	4.3818600000000000
1998-01-01	4.6337699999999990
1999-01-01	4.3699300000000000
2000-01-01	7.8314800000000000
2001-01-01	13.3746000000000000
2002-01-01	13.0790000000000000
2003-01-01	11.1278000000000000
2004-01-01	13.1740000000000010
2005-01-01	13.0256000000000000