2011

7.0

1984

6.9

2004

5.9

1971

5.7

2006

5.5

2001

5.2

2008

5.5

2008

6.1

2015

6.3

1989

5.6

2016

6.8

2000

5.0

2017

7.9

2010

5.8

1971

7.7

1997

6.5

2014

6.8

1999

7.0

1964

7.3

2001

6.0