2013

5.6

2001

5.9

2003

5.7

1988

7.3

1976

4.0

1977

4.0

1972

6.1

1972

6.7

1975

6.7

1999

6.1

2005

5.0

2006

5.2

1978

6.3

1973

7.1

1988

6.3

1994

5.8

2005

6.2

1996

5.7

2004

4.7

1971

7.1