1961

6.6

2007

6.2

1997

7.0

1992

7.3

2001

6.7

2004

7.3

1954

8.4

2005

6.3

1972

7.1

2006

6.6

1982

7.1

1987

7.1

1997

7.6

2007

6.6

1999

5.6

2002

6.6

2004

6.4

2004

6.6

2005

6.7

1988

7.7