1964

7.0

1996

4.2

1982

7.5

1984

6.6

1986

7.1

1989

5.7

1994

6.5

1996

7.3

1998

6.4

2002

6.3

2005

6.4

2003

5.8

2007

7.4

1969

7.8

1996

7.6

1970

4.5

1972

5.3

1976

4.7

2017

6.2

2004

6.5