1977

6.2

2004

6.0

2014

7.4

1987

6.7

1960

6.9

1991

6.5

1995

6.6

2017

2.6

1996

6.6

2005

6.1

1987

5.9

2007

6.7

1998

5.3

1979

6.6

2014

5.1

2009

5.5

1994

6.1

1986

6.9

1989

2.3

2002

4.8