1988

5.7

1990

7.4

1967

6.6

2014

6.2

2017

6.9

2009

8.5

1994

8.5

1971

6.0

1995

7.3

2003

7.1

2006

6.5

2001

6.4

2007

6.9

2012

6.2

2013

6.3

1995

6.9

2010

6.7

1999

8.4

2015

6.0

1963

7.0