2006

7.0

2018

4.5

2004

7.2

1996

6.5

2004

5.6

1987

7.3

1978

6.7

1975

7.3

2005

6.2

2003

5.0

2002

6.2

2005

6.5

2002

6.6

2002

6.2

2008

2.0

2001

6.6

2002

5.3

2009

5.8

1968

1.0

1973

7.2