1990

6.9

1997

6.2

1995

6.2

2016

6.1

1954

6.7

1986

5.6

1996

6.3

2004

5.7

1999

6.1

1998

5.8

2005

3.5

2007

6.0

2002

7.7

1986

5.8

2000

5.7

1959

6.7

1977

4.7

2007

6.1

1997

5.7

2004

6.3