1976

6.8

1976

2.0

1986

6.0

1968

7.5

1996

6.3

2000

4.7

2002

5.6

1995

7.7

1992

7.0

1974

7.2

1985

2.0

2011

5.0

1996

7.5

1991

7.0

1972

6.4

1984

6.6

1987

6.8

2003

7.6

1975

7.7

1987

7.1

1988

6.2

1990

7.4