1987

4.1

2005

7.2

2014

7.4

2013

6.0

2001

5.9

1975

7.5

2003

5.4

1997

6.0

1998

5.4

2017

6.3

2016

4.9

2020

10.0

2016

5.0

2004

7.1

1985

8.1

1960

7.8

1982

6.2

1998

6.2

2006

6.5

1972

7.2