1927

8.1

2003

6.1

2005

6.7

2004

6.8

2004

5.6

1979

8.3

2004

8.1

2000

7.6

2005

7.2

1968

8.1

1995

7.6

2002

7.6

2002

7.1

1997

6.7

2005

6.9