1992

7.2

1987

7.1

2002

6.6

1977

6.2

2005

5.2

1995

6.1

1984

5.6

2000

7.1

1988

5.8

2007

6.9

2007

6.9

2020

5.0

1998

7.3

1974

6.1

2008

6.8

2005

4.0

1976

0.0

2018

0.0

2010

2.8

1977

5.0