1992

6.3

1980

5.8

2015

6.1

1970

6.2

2004

7.1

1986

6.4

2012

6.1

1972

6.7

1963

7.5

1992

5.7

1958

7.1

2008

5.6

1982

7.3

1987

6.3

2011

7.1

2023

6.8

1990

6.9

1988

6.3

1968

7.3

1997

5.7