1990

4.4

2008

7.6

1987

4.1

2003

6.0

2012

6.3

2010

6.2

2021

6.2

1999

8.0

2007

7.3

2005

8.6

1987

7.3

2009

5.7

2003

6.2

1992

7.4

1957

7.2

2015

7.3

2007

6.7

1971

7.8

2010

6.1

2006

6.2