2001

6.6

2003

5.8

2003

7.2

2002

7.1

1974

6.3

2004

7.0

2011

4.9

1998

5.9

1984

6.8

1997

5.4

2014

4.8

2009

5.4

2001

5.7

2003

7.2

1968

7.4

1994

6.4

1986

6.7

2011

6.2

2011

4.8

2006

2.0