1993

6.5

1989

6.0

1977

7.2

1986

7.0

2002

7.9

2006

7.7

1987

8.4

2006

7.1

1993

7.4

1992

6.5

2001

7.7

1966

6.4

2000

7.9

2002

7.1

2006

7.4

2003

8.1

1992

7.1

2006

5.3

2000

5.0

1990

7.1