1972

6.4

2015

8.1

2002

5.4

1993

7.3

1991

5.7

2011

7.1

1988

5.4

2015

6.6

2009

4.5

2016

7.9

2010

7.4

1965

6.8

2010

7.0

2005

7.4

2007

4.8

1992

5.6

2017

5.5

2003

5.8

1986

6.4

2013

7.2