1965

7.4

2001

6.2

2013

8.0

2006

7.6

1993

5.5

2007

7.9

2001

7.8

2017

4.7

1979

6.1

2004

7.5

2003

7.0

2008

6.7

2004

7.3

2013

6.4

2001

7.9

2005

7.7

1989

5.8

1920

7.3

1985

6.2

2007

5.7