-87.61% is the change from 678 to 84
Calculation steps:
[( 84 - 678 ) ÷ 678] x 100 = -87.61%
Formula
Percentage change = [(84 - 678) / 678] x 100
Subtract the new number by the original number
84 - 678 = -594
-594 ÷ 678 = -0.8761061946902655
-0.8761061946902655 x 100 = -87.61%