-30.83% is the change from 960 to 664
Calculation steps:
[( 664 - 960 ) ÷ 960] x 100 = -30.83%
Formula
Percentage change = [(664 - 960) / 960] x 100
Subtract the new number by the original number
664 - 960 = -296
-296 ÷ 960 = -0.30833333333333335
-0.30833333333333335 x 100 = -30.83%