1991

9.2

2010

8.0

2016

7.1

2019

8.5

2012

7.6

2018

7.7

1994

6.0

1990

7.4

2001

7.6

1999

7.9

2015

8.2

2011

8.1

2013

7.6

2009

7.6

1999

7.9

2015

7.1