1998

6.1

2006

7.7

2005

7.0

1999

7.6

2007

6.4

1995

5.1

2007

6.5

2002

7.4

1984

7.1

2016

4.6

1934

7.8

1997

7.7

1989

6.0

1990

6.2

2006

6.5

1980

5.7

1977

7.0

1971

7.1

1989

6.9

1997

5.0