1996

8.7

2014

7.3

2000

6.9

2002

7.2

2008

7.7

1988

7.5

1971

8.1

1997

7.5

1994

6.0

2012

0.0

2022

8.1

1975

6.2

2005

7.0

1991

7.7

2015

6.5

2015

6.0

2014

7.2

2002

8.1

2010

7.9

2013

7.9