1990

6.9

2009

8.7

1996

8.1

2002

7.5

2012

7.6

2012

6.5

2009

7.1

1993

7.7

2016

6.9

2006

9.3

2005

7.1

1984

8.1

1996

6.1

1998

7.8

2011

8.3

2014

6.6

2011

8.4

1992

6.5

1999

7.8