2016

4.4

1983

4.0

2015

6.3

2014

7.0

1986

5.0

1991

6.2

1999

6.5

2007

1.0

1978

3.8

1977

0.0

2002

6.0

1981

1.0

1990

5.8

2005

0.0

2004

6.4