-84.42% is the change from 520 to 81
Calculation steps:
[( 81 - 520 ) ÷ 520] x 100 = -84.42%
Formula
Percentage change = [(81 - 520) / 520] x 100
Subtract the new number by the original number
81 - 520 = -439
-439 ÷ 520 = -0.8442307692307692
-0.8442307692307692 x 100 = -84.42%