1991

7.4

2003

6.0

1995

6.5

1978

6.1

2013

1.7

2004

5.2

2006

6.7

2013

6.2

2014

4.8

1970

3.8

1967

6.9

2014

6.0

2006

4.5

1969

4.6

1981

4.6

2010

5.6

1999

4.7

2014

3.0

2019

4.6

1999

4.6