1997

7.0

2004

7.5

1999

6.8

2015

5.4

1995

6.9

2005

6.2

2007

6.6

2019

6.8

1991

6.7

2006

4.4

2006

3.5

2002

6.1

1967

6.0

2003

7.1

1980

6.8

2000

7.1

2007

6.7

1997

7.6

1970

3.5

2021

0.0