1993

8.1

2004

7.2

1996

5.2

2003

6.4

1979

8.0

2007

5.0

1999

6.0

2017

10.0

1987

6.5

2007

7.0

2006

6.8

1994

7.4

2009

5.9

2017

6.5

1998

6.2

2009

5.9

1966

6.9

1982

4.5

1983

5.7

2015

6.8