1989

7.8

1986

7.2

1990

7.5

1996

7.3

1984

7.7

1978

7.5

1998

6.8

1985

8.3

2000

7.3

1979

6.5

1995

7.6

1996

4.2

2018

7.0

1991

8.1

2003

6.2

1979

8.2

1963

7.4

1997

7.6

1972

6.4

2002

6.0