1977

5.4

2017

7.8

1982

6.7

1989

6.2

2015

7.8

2015

6.1

2012

7.0

2013

8.4

2005

5.2

2012

5.8

2008

7.7

1999

4.6

1984

7.2

2011

7.1

2010

6.6

2002

9.1

2011

6.6

2001

7.2

1955

7.2

2003

5.3