2017

7.3

2018

6.4

2019

6.5

1984

7.0

1991

8.3

1994

8.7

1985

7.0

1984

8.4

2003

7.7

1999

7.5

2006

7.4

1981

8.1

2005

7.0

1997

7.4

1986

7.5

1953

8.0

1955

7.6

1983

7.2

1930

7.3

1986

7.9