1953

7.2

1988

6.5

1997

4.5

2012

7.7

1992

6.4

2018

5.2

1963

6.9

2013

5.9

1991

6.1

2017

5.9

2015

7.6

2017

7.8

1988

6.1

1975

6.4

1993

6.5

1980

6.8

1968

6.4

2001

8.9

2010

6.3

1984

7.2