1999

7.5

2017

6.7

2012

6.0

1968

1.0

2006

6.2

1973

3.5

2001

7.4

1991

5.7

2006

7.4

2007

6.5

2006

6.3

1992

7.4

1930

6.8

2005

4.9

2002

6.3

1973

5.0

2004

6.7

1991

4.7

2016

5.1

1972

6.2