2007

6.4

1987

4.1

2005

7.2

1992

6.7

2013

6.0

1975

7.5

1998

5.7

2003

5.4

2017

6.3

2004

7.1

1985

8.1

1960

7.8

1982

6.2

2009

6.2

2006

6.5

1972

7.2

2007

6.8

2002

5.8

1961

8.1

2020

7.0