1988

6.5

2006

5.2

2005

6.2

1987

6.1

2002

6.3

2003

6.5

2011

0.0

2001

6.6

1997

6.0

1999

5.1

2005

6.2

1983

7.1

1983

7.4

2004

5.6

1973

7.1

2006

5.9

1999

6.5

1994

5.3

1998

6.3

1994

6.7