1959

7.3

1997

7.0

2005

7.5

1982

6.7

2004

7.8

2006

6.8

1986

7.3

1955

7.2

1989

6.3

1980

7.7

1994

8.7

1999

7.5

1991

7.3

1980

7.1

1997

6.8

1934

6.1

1986

2.8

2001

5.9

1955

7.9

2001

6.3