1965

6.3

1994

8.7

1999

8.4

2017

7.3

2019

7.7

2018

6.9

2008

8.5

1981

7.9

1993

7.6

2016

7.9

2012

6.4

2014

8.5

1977

8.2

2018

7.5

2003

8.5

1958

8.2

1971

8.2

2009

8.0

2015

7.3

2019

8.1