2009

5.1

1998

6.7

1998

6.3

1989

6.3

1990

5.5

1997

6.5

2007

6.7

2000

5.2

1994

6.8

2003

6.9

1996

7.3

1986

6.1

2001

5.6

1976

6.5

2014

4.7

1995

6.2

2004

6.2

1993

6.3

1925

6.0

2001

6.8