1998

7.2

1990

7.0

1995

7.6

1980

6.5

1992

6.9

1998

7.0

2012

7.8

2006

7.8

2010

8.2

1989

8.4

1999

8.0

2001

8.1

1960

7.1

2017

8.4

2011

8.1

2021

7.7

2015

7.8

1962

7.3

2008

8.1

1999

6.9