1976

6.3

1981

7.0

2000

7.4

2006

6.2

1996

5.2

2009

4.3

1991

5.4

1949

6.7

2002

5.7

1994

3.4

1980

5.5

1995

4.0

1998

6.7

2000

6.0

2005

6.0

1971

6.4

1993

6.2

2021

5.8

1987

6.5

1995

7.3