1978

7.0

1993

5.5

1995

6.8

2002

4.5

2009

4.1

2010

5.1

2014

6.6

2004

6.8

2006

5.2

2012

6.2

2013

7.2

2003

6.7

2012

7.3

6.0

1997

5.6

2016

6.5

2018

2.0

1942

7.4

2006

5.8

2003

6.2