-28.78% is the change from 938 to 668
Calculation steps:
[( 668 - 938 ) ÷ 938] x 100 = -28.78%
Formula
Percentage change = [(668 - 938) / 938] x 100
Subtract the new number by the original number
668 - 938 = -270
-270 ÷ 938 = -0.2878464818763326
-0.2878464818763326 x 100 = -28.78%