-83.69% is the change from 515 to 84
Calculation steps:
[( 84 - 515 ) ÷ 515] x 100 = -83.69%
Formula
Percentage change = [(84 - 515) / 515] x 100
Subtract the new number by the original number
84 - 515 = -431
-431 ÷ 515 = -0.8368932038834952
-0.8368932038834952 x 100 = -83.69%