1977

6.7

2005

7.8

2009

5.9

2002

4.5

2019

5.4

2016

7.0

2006

6.9

2007

7.3

2010

7.7

2009

5.9

2005

5.2

2008

8.7

2018

6.4

2018

6.4

2007

6.2

2009

7.7

1971

7.0

1993

7.0

1994

6.5

2015

6.5