1962

7.2

1979

7.4

1989

8.0

2005

7.6

1998

7.0

1989

8.1

2002

8.3

1989

8.3

2008

6.2

1993

8.0

2005

6.8

2020

7.3

1977

7.4

1986

7.7

2003

8.2

1997

7.7

2003

5.5

2004

5.9

1993

7.9

1984

7.8