2001

7.2

2010

6.6

2016

6.7

2005

5.2

2003

5.7

2013

6.2

1989

5.5

1982

6.7

1956

7.5

2015

8.4

1952

7.7

2009

6.1

1995

5.6

2012

8.2

2006

7.4

1953

6.9

2011

7.6

1983

7.4

1975

6.8

1990

6.1