1975

3.1

1994

5.9

2008

5.9

2006

4.6

2019

6.0

2002

5.2

2015

5.9

2006

6.9

2004

4.7

2008

5.3

1999

6.8

1985

7.7

2025

10.0

1952

7.9

2003

7.2

1999

7.1

1986

6.7

1995

7.2

1977

3.4

2016

6.4