1981

5.2

1990

6.7

1996

6.5

1993

3.0

1997

5.9

2002

6.3

2008

2.0

2007

0.0

2006

5.2

2001

6.3

1987

0.0

1985

0.0

1994

7.0

2015

6.9

2003

10.0

1991

5.7

1995

4.8

2010

5.2

2009

6.2

1987

4.0

2013

7.2

1990

2.0

1995

5.0

1995

7.8

1989

0.0

1992

3.4