1994

6.5

2000

4.9

2011

5.1

1945

7.2

1998

6.5

1977

6.7

1970

6.0

2012

9.8

1990

5.8

2013

7.6

1987

6.2

2009

4.4

2017

6.0

2003

7.8

2008

7.1

2009

8.5

1953

6.8

2012

9.4

2016

6.8

2005

5.7