1990

6.1

1951

7.2

1999

6.4

1996

6.6

1999

6.2

2009

5.2

2010

6.2

1979

6.8

2008

3.9

1998

6.0

2012

6.5

1968

6.9

2017

4.5

2000

6.7

2003

5.5

2002

6.3

1961

7.2

1958

7.0

2008

5.1

1941

7.0