1991

7.6

1995

7.3

1980

8.2

1997

7.8

1993

6.9

2000

6.1

2006

5.2

2006

5.4

1997

6.1

1993

7.5

1994

7.6

1998

8.3

1957

8.5

2023

6.5

2020

5.0

1972

7.5

2005

6.2

1941

7.1

2019

7.0

2021

8.0