2008

6.8

2015

6.0

1990

6.1

2007

4.9

2004

6.6

2013

6.7

2001

6.5

2007

6.5

1998

5.9

2011

5.7

1965

6.0

1991

6.4

1972

7.5

2009

7.2

2015

5.9

2004

7.1

2004

4.8

1991

5.9

2011

6.0

2015

7.0