-23.99% is the change from 521 to 396
Calculation steps:
[( 396 - 521 ) ÷ 521] x 100 = -23.99%
Formula
Percentage change = [(396 - 521) / 521] x 100
Subtract the new number by the original number
396 - 521 = -125
-125 ÷ 521 = -0.2399232245681382
-0.2399232245681382 x 100 = -23.99%