2003

7.6

1991

7.5

2007

5.2

2004

5.9

2006

5.5

2007

6.0

1992

4.4

2001

5.4

1999

6.8

1968

6.0

2003

3.5

1993

7.6

1988

1.0

2010

6.3

2005

5.8

1969

5.0

1999

5.5

1975

5.5

2000

0.0

1958

0.0