1970

7.3

2003

7.3

1979

7.6

2000

6.4

1999

5.1

2009

7.4

2013

6.9

1953

7.2

2021

4.7

1980

7.5

2010

7.2

2005

6.7

1983

6.6

1959

7.4

2003

7.2

2006

6.8

1991

7.0

1996

5.8

2001

6.8

2011

7.8