1986

8.5

1996

7.7

1997

8.0

1979

7.5

2006

7.2

2005

7.6

1996

7.7

1981

6.9

2011

8.6

2016

7.5

2010

7.6

2006

7.1

1993

7.4

2000

6.2

1986

8.2

1995

7.3

2017

6.5

2014

7.3

1983

7.8

2019

8.2