-3.33% is the change from 691 to 668
Calculation steps:
[( 668 - 691 ) ÷ 691] x 100 = -3.33%
Formula
Percentage change = [(668 - 691) / 691] x 100
Subtract the new number by the original number
668 - 691 = -23
-23 ÷ 691 = -0.03328509406657019
-0.03328509406657019 x 100 = -3.33%