1965

7.1

2010

7.8

1986

7.9

1988

7.7

2005

5.8

2004

6.2

1989

5.9

1996

7.2

2003

7.3

2013

6.6

2008

6.7

2012

6.6

2006

5.9

2019

6.8

1970

7.3

2012

6.3

2003

6.1

1987

7.5

2012

6.3

2015

6.9