1994

6.7

2006

7.6

1987

6.9

2003

5.0

2017

5.3

2013

6.0

1990

6.4

2002

6.8

1967

7.3

1976

7.0

1969

6.7

2004

6.0

1934

7.5

1999

7.0

2002

6.6

2004

6.4

1992

6.2

2005

6.2

1999

6.5

2002

7.8