2003

8.7

2015

5.1

2001

5.9

2010

6.9

2013

7.2

1988

5.2

1983

7.9

2010

6.9

2002

5.6

1980

7.8

1989

7.3

2011

6.6

2003

5.1

1994

6.2

1996

5.4

2009

6.5

1990

5.5

1993

5.7