-19.77% is the change from 521 to 418
Calculation steps:
[( 418 - 521 ) ÷ 521] x 100 = -19.77%
Formula
Percentage change = [(418 - 521) / 521] x 100
Subtract the new number by the original number
418 - 521 = -103
-103 ÷ 521 = -0.19769673704414586
-0.19769673704414586 x 100 = -19.77%