2000

6.2

2017

8.3

2008

8.5

2007

6.3

1979

7.7

1969

7.6

1968

8.1

2011

7.2

2008

7.2

2009

4.7

2008

7.3

1999

6.8

2014

8.0

1990

6.3

1985

7.1

1971

6.4

1995

6.0

2013

6.8

1996

7.4

2016

4.9