-33.61% is the change from 970 to 644
Calculation steps:
[( 644 - 970 ) ÷ 970] x 100 = -33.61%
Formula
Percentage change = [(644 - 970) / 970] x 100
Subtract the new number by the original number
644 - 970 = -326
-326 ÷ 970 = -0.33608247422680415
-0.33608247422680415 x 100 = -33.61%