-84.07% is the change from 810 to 129
Calculation steps:
[( 129 - 810 ) ÷ 810] x 100 = -84.07%
Formula
Percentage change = [(129 - 810) / 810] x 100
Subtract the new number by the original number
129 - 810 = -681
-681 ÷ 810 = -0.8407407407407408
-0.8407407407407408 x 100 = -84.07%