-96.35% is the change from 521 to 19
Calculation steps:
[( 19 - 521 ) ÷ 521] x 100 = -96.35%
Formula
Percentage change = [(19 - 521) / 521] x 100
Subtract the new number by the original number
19 - 521 = -502
-502 ÷ 521 = -0.963531669865643
-0.963531669865643 x 100 = -96.35%