2002

6.4

1992

5.0

2004

3.8

1998

5.8

1977

4.1

2017

6.7

2008

6.8

1991

5.8

1989

6.0

2011

5.1

2009

6.0

2015

4.6

1984

5.3

1994

7.1

1939

5.7

1973

4.8

1985

4.3

1944

4.0

1975

6.4