1984

4.3

1982

6.2

1974

5.5

1973

5.3

2003

4.0

1985

6.6

1985

5.8

1985

5.9

1993

6.3

2003

6.5

2006

6.1

2004

5.7

2009

7.3

2006

5.3

2016

5.1

1989

7.1

2008

5.7

1983

6.0

1977

4.7

2004

5.0