1998

6.6

2003

6.5

1990

6.8

2006

6.3

1976

3.3

1969

2.8

2008

6.2

2006

6.0

1997

6.1

2006

5.8

1976

5.6

1930

6.8

1997

3.5

1977

7.4

1976

1.0

1979

5.3

2004

5.5

2001

6.2

2005

6.2

1981

5.4