1997

6.2

2006

6.8

2005

6.5

1988

7.1

1983

4.7

1995

7.0

2016

4.0

2002

6.2

1997

6.8

1972

6.0

2004

6.0

1964

5.0

1994

3.2

1977

3.8

1980

6.4

1992

6.2

2014

5.1

1961

5.6

1974

4.0

2004

3.6