Year	Percent
1980-01-01	3.80
1981-01-01	3.85
1982-01-01	2.39
1983-01-01	2.61
1984-01-01	2.04
1985-01-01	2.18
1986-01-01	3.78
1987-01-01	5.60
1988-01-01	4.69
1989-01-01	7.00
1990-01-01	5.15
1991-01-01	3.91
1992-01-01	5.52
1993-01-01	3.15
1994-01-01	2.43
1995-01-01	2.59
1996-01-01	2.15
1997-01-01	1.99
1998-01-01	2.15
1999-01-01	2.18
2000-01-01	1.88
2001-01-01	1.66
2002-01-01	1.74