2002

7.7

1995

8.2

1999

7.1

1994

7.8

1977

8.6

2010

7.8

2008

7.8

2012

7.5

2010

7.9

1997

7.7

2014

7.9

2000

7.2

2010

7.0

2003

7.8

2010

8.0

2012

6.3

1989

5.9

2016

7.5

1974

7.0

1990

6.9