2003

6.8

2005

7.3

2007

6.7

2004

6.6

1968

6.2

2002

6.8

2007

6.8

1969

6.9

1987

6.0

1955

6.3

2000

7.3

1986

6.7

1981

5.9

2002

5.7

1985

7.5

1990

6.7

1987

6.8

2004

5.6

1991

6.6

1980

6.9