1988

5.2

2004

5.7

2011

5.5

1975

6.9

1986

5.8

1981

6.2

1942

5.8

2004

7.8

1999

6.0

2005

6.1

1972

6.7

2001

6.2

1998

6.0

2004

6.2

2023

6.7

2012

7.1

2014

6.5

2008

6.4

1998

5.0

2006

5.5