Exactly −1

−0.70

−0.50

−0.30

0

+0.30

+0.50

+0.70

Exactly +1

A perfect downhill (negative) linear relationship

A strong downhill (negative) linear relationship

A moderate downhill (negative) relationship

A weak downhill (negative) linear relationship

No linear relationship

A weak uphill (positive) linear relationship

A moderate uphill (positive) relationship

A strong uphill (positive) linear relationship

A perfect uphill (positive) linear relationship