1993

6.4

1990

7.9

1972

5.3

2007

7.6

1980

8.2

1997

7.5

2004

7.8

2011

6.1

2001

5.9

1958

8.2

2003

6.3

2007

7.2

2013

7.7

1991

7.6

1997

8.2

2004

6.2

2012

7.3

2009

7.3

1998

6.6

2012

6.6