1987

7.3

1983

7.6

2017

6.0

2017

6.2

1989

6.1

2016

6.9

1984

6.8

1971

7.2

1991

4.9

2000

6.7

1986

5.4

2000

7.0

1983

5.1

2005

6.6

2003

7.2

2004

6.3

2008

7.1

1992

6.2

1998

5.7

2017

7.3