2005

6.7

1998

6.6

2006

6.3

2003

5.8

2003

6.4

1990

6.7

2000

3.0

1972

3.7

2002

7.1

2000

7.1

2004

7.2

2006

7.0

2003

6.0

2005

5.9

2001

6.7

2004

6.3

1997

6.8

2005

6.7

2017

4.9

1968

3.0