2011

6.5

2007

6.4

1988

6.5

1964

7.0

1994

6.2

2010

5.6

2009

5.3

2006

5.5

1985

6.6

2009

5.6

2006

6.2

1985

5.4

1999

6.1

2008

6.2

2015

8.0

1994

6.2

2005

6.8

1995

5.9

2000

7.0

1997

6.2