1975

5.5

1972

3.9

1978

3.4

1991

1.0

2003

6.2

2005

5.5

2006

5.5

2007

5.7

2002

5.5

2001

6.2

1974

4.2

2005

6.4

1973

5.3

2002

5.4

1971

5.6

1999

6.6

1990

4.0

1973

4.5

1975

0.0

1977

3.4