1997

6.7

2004

5.9

1999

6.7

2002

4.8

2001

6.0

2005

6.0

1987

6.8

1981

6.5

1978

6.7

1996

6.0

2021

6.0

1994

7.0

1999

6.1

1983

6.2

1999

5.5

1960

7.6

1998

7.2

2000

6.3

1998

7.1

1966

6.8