1963

6.9

1990

6.1

1982

6.8

2020

6.4

1984

6.6

2000

6.1

2010

9.1

1999

5.1

2001

6.7

1988

5.7

1994

6.6

2011

7.2

1966

7.0

2004

5.8

2009

6.1

2008

6.2

1972

4.0

1993

6.7

2011

6.6

2009

5.1