-27.47% is the change from 921 to 668
Calculation steps:
[( 668 - 921 ) ÷ 921] x 100 = -27.47%
Formula
Percentage change = [(668 - 921) / 921] x 100
Subtract the new number by the original number
668 - 921 = -253
-253 ÷ 921 = -0.2747014115092291
-0.2747014115092291 x 100 = -27.47%