1981

5.2

1990

6.3

1995

5.8

2008

2.7

2018

5.8

2001

5.4

1999

5.2

2013

4.4

2018

7.4

2003

5.0

2015

4.9

1978

4.7

2014

7.8

2019

4.8

1977

3.9

2011

3.6

2010

5.7

1977

5.7

2011

5.4

2024

1.0