1960

8.4

1994

5.8

1987

6.7

2002

6.4

1983

6.5

2003

6.6

1993

6.6

1962

7.9

1964

7.3

2001

6.1

1969

6.1

1973

6.9

2004

6.1

1995

7.2

1986

5.6

2001

7.2

1991

7.3

2005

6.8

1964

7.2

1996

6.0