1960

6.7

1998

6.1

2005

6.8

2007

6.9

2018

6.7

2013

7.3

2003

7.0

2002

4.5

2015

5.9

2019

6.6

2005

7.2

1997

7.7

2009

6.4

2009

5.5

1928

8.0

1983

6.6

2015

6.0

2014

5.7

1955

8.0

2017

5.9