1996

6.6

2000

5.0

2005

3.6

1999

6.8

2001

6.9

1993

5.0

2006

6.6

1999

7.5

2007

6.7

1996

7.0

1998

7.2

1992

7.4

2006

6.6

2012

3.0

2020

6.9

1986

7.6

2003

5.9

2001

6.1

1982

0.0

2002

7.2