-23.61% is the change from 521 to 398
Calculation steps:
[( 398 - 521 ) ÷ 521] x 100 = -23.61%
Formula
Percentage change = [(398 - 521) / 521] x 100
Subtract the new number by the original number
398 - 521 = -123
-123 ÷ 521 = -0.236084452975048
-0.236084452975048 x 100 = -23.61%