1987

6.3

2005

6.3

1975

5.8

2002

7.1

1970

5.5

2018

5.6

2007

6.1

2019

7.1

2006

7.8

2019

7.3

1996

8.0

2015

5.2

2001

4.4

1995

7.6

1987

8.6

1936

7.2

1990

9.0

2014

6.9

1928

0.0

1964

0.0