2007

6.7

2013

4.0

2014

6.2

2006

7.5

2005

6.4

1963

7.1

1967

6.6

1974

6.4

1981

6.5

2006

6.3

2003

6.3

2001

6.9

2021

6.0

2002

5.4

2008

5.2

1990

6.1

1995

7.7

1998

6.5

1990

5.8

1976

6.1