1973

5.9

2009

5.9

1980

5.2

1971

5.4

1977

4.7

1979

6.4

2005

5.6

1986

5.1

1989

4.9

2013

0.0

1997

5.7

1982

5.7

2005

6.6

2007

7.1

1985

7.8

1980

6.3

2008

5.0

2005

6.2

2012

6.0

2007

5.6