1962

6.9

1964

7.0

1971

6.4

2005

6.8

1955

6.0

2001

6.8

2003

5.6

2005

7.4

1997

6.6

1978

6.0

1987

4.1

2004

7.3

2007

6.4

1985

6.2

2000

5.5

2002

5.6

1995

5.2

2021

5.4

1988

6.4

1983

6.5