1976

7.5

1977

6.7

1989

4.5

2003

5.4

2001

5.0

1982

4.6

1997

5.5

1985

4.7

2012

6.3

1986

5.4

1987

4.3

1990

6.0

2001

5.1

2007

3.0

2004

6.8

1998

5.8

1983

0.0