1993

5.5

2015

4.6

1996

7.5

1998

8.4

2017

6.0

2001

6.4

2007

5.4

2014

5.7

1974

7.1

2012

7.0

2006

7.2

2016

7.4

1951

7.6

1972

7.3

2014

5.6

2020

7.2

2014

4.6

2017

8.5

2015

6.7

1980

5.8