1980

0.0

1989

8.2

2020

8.1

2012

7.5

1974

6.9

2009

7.0

1997

7.5

1979

5.0

1983

0.0

1975

5.7

1986

0.0

1982

6.7

1983

3.0

2008

7.7

1969

7.7

2011

4.0

2021

6.9