1984

6.1

2010

8.4

2012

7.7

2008

8.5

2000

7.0

2009

7.4

2014

8.4

2015

6.7

1998

8.1

1999

8.4

1985

8.3

2003

6.7

2016

6.9

2012

7.8

2020

7.2

1959

6.9

2001

8.5

2013

7.3

2007

7.2

2014

7.6