1979

5.0

1978

6.4

1997

4.6

1955

6.0

1989

5.3

2002

3.4

2003

5.8

2016

7.6

1997

6.2

2006

7.1

1996

6.3

2006

6.3

1983

6.7

2008

6.7

1977

5.6

2007

6.9

1974

7.0

1983

6.5

1951

6.3

2014

7.4