1996

8.0

2006

7.8

2002

7.1

2005

6.3

2005

7.5

2001

4.3

1987

7.7

1995

7.6

1987

6.1

2015

5.1

1997

3.5

2017

7.0

2007

6.1

1936

7.1

2015

6.3

1992

5.0

1999

5.0

2018

6.0

2020

7.7

2004

5.7