2000

7.2

1990

7.4

2006

6.2

1987

7.5

2003

6.2

2008

5.9

2012

4.5

2014

6.2

2011

5.5

1944

7.6

1968

6.6

1988

6.0

2001

7.1

2012

6.9

1984

6.6

2012

6.4

1984

7.7

2005

6.3

1988

6.2

2011

5.7