1972

6.4

2003

5.7

1982

5.7

2000

5.2

2012

7.6

2002

5.4

1994

5.7

1960

7.5

1987

6.5

1888

4.9

2005

6.3

1973

6.2

1991

5.7

2015

7.1

2008

6.7

1959

7.8

2009

4.7

1996

5.2

2000

6.3

2016

6.8