1983

8.0

2001

7.7

2004

7.3

2006

7.8

2006

6.8

1990

7.7

1997

6.1

2017

7.4

1991

0.0

1977

0.0

1997

4.8

1982

6.7

1953

7.0

1984

6.9

2015

4.6

2005

7.1

2018

9.0

2007

5.0

1968

7.6

1976

6.2