1981

7.4

2004

7.3

2011

6.5

2010

7.5

1975

8.0

1966

8.5

1990

7.0

2014

8.5

2006

5.9

2005

6.7

2011

6.8

1991

5.9

2012

8.2

2002

7.3

2024

6.3

2012

6.9

2009

7.1

2017

5.9

2006

7.7

1999

7.6