1967

6.5

2004

5.8

1999

6.6

2000

6.7

1988

7.3

1993

5.5

1994

5.9

1980

6.7

1951

6.4

1987

5.5

1990

5.5

2012

4.6

1978

6.0

2014

6.5

1966

6.5

2002

6.1

2001

5.2

2004

6.2

1968

7.1

1997

6.5