7.8

2002

4.7

2007

6.4

1986

6.2

1993

4.6

2017

5.4

2006

5.8

2016

6.9

2009

7.5

2013

8.1

1999

7.2

2017

8.0

2015

6.4

2007

7.6

2009

6.6

2007

9.0

1998

5.5

2001

6.5

2012

6.3