1997

7.0

1989

6.3

2003

4.9

2001

6.7

2015

4.7

2003

6.5

1998

6.0

2004

5.1

1999

6.6

1992

6.1

1981

6.4

1996

4.4

2009

0.0

2014

6.4

1985

4.0

1976

6.8

2008

2.0

2014

7.4

2008

3.3

2007

6.6