1969

7.4

2001

7.9

2018

8.0

1977

7.7

2001

5.8

1991

7.6

1972

8.7

2016

7.9

2013

7.9

2007

6.4

2008

7.8

1984

7.3

2014

7.5

2015

6.3

1993

7.7

1988

7.8

1994

8.5

1994

8.7

1976

7.8

2001

8.5