1968

6.4

2009

6.1

2020

7.0

2019

6.8

2013

6.2

2012

5.8

2007

5.6

1965

7.1

2016

7.0

1988

7.2

2007

4.8

2003

7.8

1984

7.2

2004

5.7

2008

7.4

1994

8.7

2004

7.5

1966

6.5

2014

8.5

1997

4.6