-12.3% is the change from 878 to 770
Calculation steps:
[( 770 - 878 ) ÷ 878] x 100 = -12.3%
Formula
Percentage change = [(770 - 878) / 878] x 100
Subtract the new number by the original number
770 - 878 = -108
-108 ÷ 878 = -0.12300683371298406
-0.12300683371298406 x 100 = -12.3%