-97.61% is the change from 878 to 21
Calculation steps:
[( 21 - 878 ) ÷ 878] x 100 = -97.61%
Formula
Percentage change = [(21 - 878) / 878] x 100
Subtract the new number by the original number
21 - 878 = -857
-857 ÷ 878 = -0.9760820045558086
-0.9760820045558086 x 100 = -97.61%