1976

7.0

1982

7.3

1992

6.7

1966

6.6

1968

7.4

1986

7.9

1982

5.1

1993

6.1

2005

7.0

1966

7.4

2001

6.6

1984

6.1

1969

5.5

2001

6.8

1997

5.2

1965

7.3

1982

5.0

2006

7.0

1984

7.4

2013

0.0