2007

6.5

1988

5.8

1955

7.2

1995

6.2

2010

7.1

1997

5.4

1968

6.8

1976

6.7

2007

7.0

1985

6.5

1988

6.7

2007

6.0

1975

6.8

1982

6.4

2008

5.8

1992

7.4

2004

7.3

1989

5.6

2017

6.6

2006

6.3