1966

8.2

2005

7.0

1994

7.6

1979

7.6

2004

6.8

1991

6.5

1978

7.0

1993

6.7

2002

6.6

1976

7.6

2001

5.4

1986

6.5

2001

6.5

1973

7.2

2018

7.1

2006

7.5

1999

7.4

1998

5.9

2001

7.8

2005

6.2