-51.39% is the change from 866 to 421
Calculation steps:
[( 421 - 866 ) ÷ 866] x 100 = -51.39%
Formula
Percentage change = [(421 - 866) / 866] x 100
Subtract the new number by the original number
421 - 866 = -445
-445 ÷ 866 = -0.5138568129330254
-0.5138568129330254 x 100 = -51.39%