2004

5.6

1987

7.3

1999

7.4

2003

5.8

1988

4.9

1988

5.9

1979

7.5

2018

3.3

2009

6.1

2000

6.0

1976

5.9

1992

3.0

1972

5.6

2008

5.8

2005

5.4

2015

6.9

1996

6.1

2015

3.8

1973

3.8

1971

6.7