1996

4.0

2002

6.8

1983

5.0

1975

5.5

2006

6.2

1990

6.5

2007

5.4

2005

6.3

1992

5.9

2009

6.6

1997

6.0

2014

6.0

2014

5.2

1984

1.0

1986

5.5

2020

7.0

1969

2.3

2018

6.5

2003

4.5

1976

5.7