Year	Percent
1975-12-31	10.63
1976-12-31	13.63
1977-12-31	6.34
1978-12-31	12.22
1979-12-31	16.75
1980-12-31	14.25
1981-12-31	14.84
1982-12-31	9.94
1983-12-31	8.86
1984-12-31	9.14
1985-12-31	11.23
1986-12-31	10.68
1987-12-31	8.39
1988-12-31	12.64
1989-12-31	13.35
1990-12-31	13.35
1991-12-31	10.28
1992-12-31	6.58
1993-12-31	5
1994-12-31	6.3
1995-12-31	6.28
1996-12-31	6.22
1997-12-31	7.31
1998-12-31	5.88
1999-12-31	5.69
2000-12-31	5.79
2001-12-31	3.92
2002-12-31	3.9
2003-12-31	3.93
2004-12-31	4.76