1988

5.1

1998

7.8

2016

5.5

1982

5.5

1987

4.7

1973

4.8

1996

6.6

2002

7.1

2005

6.3

2001

6.7

1994

2.5

1986

5.8

1993

3.5

2004

4.9

1981

6.5

1998

4.5

2006

5.4

2004

4.8

2013

6.7

2001

6.2