1981

9.0

2003

6.7

1965

6.7

2004

6.6

2009

5.9

1920

7.3

2000

6.1

2007

6.4

2011

5.7

2015

5.3

2015

7.2

2004

5.9

2003

6.5

1992

8.1

2014

5.9

1997

6.3

2004

7.3

2013

5.5

1998

6.6

2001

7.4