2018

6.7

2003

5.9

2008

7.4

2010

6.8

2010

7.9

2007

7.7

2005

5.2

1997

5.4

1951

7.2

1961

7.2

1999

7.3

2009

7.8

1968

6.8

2013

7.2

1980

6.2

2016

6.9

1992

6.1

1991

5.8

2004

6.6

2012

6.3