1972

5.8

1983

7.3

2012

7.2

2009

5.7

2010

6.3

2018

6.7

1995

7.3

1986

6.9

1999

6.6

2014

5.8

1996

6.6

2011

6.1

2017

6.8

2012

7.2

2012

5.8

1984

7.4

1985

6.2

1986

5.8

2016

7.5

2015

7.3