1980

0.0

2005

7.8

1996

8.5

1994

8.2

2005

7.3

2011

9.0

1995

7.2

1986

8.0

2002

7.5

2020

0.0

2006

7.3

2002

8.1

2020

8.2

1991

6.9

1981

8.1

2003

7.5

1996

6.4

1995

8.2

2001

6.6

1999

7.8