-31.55% is the change from 970 to 664
Calculation steps:
[( 664 - 970 ) ÷ 970] x 100 = -31.55%
Formula
Percentage change = [(664 - 970) / 970] x 100
Subtract the new number by the original number
664 - 970 = -306
-306 ÷ 970 = -0.3154639175257732
-0.3154639175257732 x 100 = -31.55%