1975

6.5

1996

1.0

1967

6.2

1997

3.0

1995

6.0

2016

5.1

2014

5.8

2001

1.3

1995

5.7

2004

3.8

1979

3.5

1973

4.7

1977

5.4

2004

5.2

2000

6.3

2013

5.8

1999

6.3

1983

4.3

2016

7.0

2010

6.4