Year	Percent
1980-01-01	2.75
1981-01-01	2.88
1982-01-01	2.50
1983-01-01	2.21
1984-01-01	2.25
1985-01-01	2.25
1986-01-01	2.25
1987-01-01	2.25
1988-01-01	2.25
1989-01-01	2.00
1990-01-01	2.25
1991-01-01	2.25
1992-01-01	2.75
1993-01-01	2.00
1994-01-01	1.50
1995-01-01	1.50
1996-01-01	2.00
1997-01-01	2.00
1998-01-01	1.75