-69.28% is the change from 866 to 266
Calculation steps:
[( 266 - 866 ) ÷ 866] x 100 = -69.28%
Formula
Percentage change = [(266 - 866) / 866] x 100
Subtract the new number by the original number
266 - 866 = -600
-600 ÷ 866 = -0.6928406466512702
-0.6928406466512702 x 100 = -69.28%