1996

6.9

1987

7.5

1952

6.9

2005

7.3

1980

8.1

1992

7.1

2002

5.3

2000

7.2

2001

7.5

2007

7.7

2019

5.8

2007

6.3

1997

7.6

2003

6.1

2000

6.6

1991

6.8

1970

4.2

2002

6.7

2000

6.0

2014

4.9