1988

7.3

2004

6.9

2009

6.5

1980

6.3

2005

4.3

2002

6.2

1986

7.0

2021

6.8

2017

6.3

1978

6.3

1994

5.8

1989

7.1

1975

6.8

2003

6.1

1980

5.7

1975

1.0

2005

6.2

1986

6.2

1984

5.4

2003

5.8