2003

5.1

2001

7.5

1983

5.8

1991

7.2

2008

6.6

1997

6.5

1995

6.2

1998

7.0

1997

6.0

1978

7.2

1966

6.7

1997

4.3

2007

6.5

2001

6.7

1999

6.9

2003

5.5

2008

6.3

1995

7.2

2003

6.3

1953

6.8