-10.16% is the change from 866 to 778
Calculation steps:
[( 778 - 866 ) ÷ 866] x 100 = -10.16%
Formula
Percentage change = [(778 - 866) / 866] x 100
Subtract the new number by the original number
778 - 866 = -88
-88 ÷ 866 = -0.10161662817551963
-0.10161662817551963 x 100 = -10.16%