-77.93% is the change from 521 to 115
Calculation steps:
[( 115 - 521 ) ÷ 521] x 100 = -77.93%
Formula
Percentage change = [(115 - 521) / 521] x 100
Subtract the new number by the original number
115 - 521 = -406
-406 ÷ 521 = -0.7792706333973128
-0.7792706333973128 x 100 = -77.93%