1973

8.3

1993

7.3

1984

7.2

1987

6.9

2005

6.0

2006

6.8

1963

7.0

2006

5.6

1984

7.3

1971

4.5

2014

5.8

1983

6.9

1986

6.3

2000

5.5

2003

6.1

1999

6.2

1996

6.8

1998

6.6

2015

6.1

2016

4.9