1979

5.5

2013

8.0

1998

5.4

1993

6.5

2003

5.7

1976

6.7

1998

7.3

1983

6.4

1984

7.4

2008

3.1

1982

7.5

1997

3.0

1972

7.9

1986

7.1

2004

5.3

1986

5.5

1999

6.1

1997

3.3

2003

7.8

1997

5.0

2000

7.6

2010

7.4

2013

7.4

2005

7.1

1998

4.2

1981

7.5

1977

7.2

2011

3.8

2007

3.5

1982

6.4

2011

5.9

1996

5.0

1996

7.0

2006

5.3

1983

6.8