1991

6.0

2008

4.2

2003

0.0

1997

5.0

2002

6.5

2002

6.5

1989

4.9

2007

3.5

2003

7.6

2002

4.3

1978

5.5

2009

6.6

2004

6.1

2013

5.2

2015

6.0

2006

5.7

1999

3.8

1994

10.0