1997

5.4

1988

5.2

1993

4.8

2011

6.3

2011

7.5

2023

6.2

1988

6.5

2011

6.5

2006

7.0

2024

7.1

1994

6.0

2009

6.4

1986

7.6

2002

6.5

2024

6.5

1965

6.8

1968

6.6

1991

6.9

1977

6.8

2013

6.9