1988

4.7

2016

9.0

2014

5.7

1997

3.0

1980

4.3

1986

6.4

1991

4.8

1996

5.5

1987

5.3

1976

4.7

1999

7.3

1994

5.0

2004

5.3

2008

5.1

2005

5.1

2003

5.4

1966

7.7

2012

3.7

2007

5.0

1981

6.9