1986

6.4

2017

7.5

1986

6.0

2003

6.3

1999

6.5

1986

6.3

2007

6.2

2003

7.4

1997

6.5

1978

6.8

2002

6.5

1981

6.4

2002

6.3

2004

6.1

2002

5.9

1991

7.3

2006

5.5

2010

6.2

1960

6.3

2006

4.2