1931

5.8

2019

6.7

2008

5.4

2005

5.2

1970

6.0

1963

6.9

2014

7.0

1962

6.9

1999

5.1

1969

4.7

2001

7.5

2003

6.8

2006

7.0

2000

6.7

1994

6.6

2007

7.4

2009

5.4

2017

6.2

1998

6.1

1999

6.0