-40.12% is the change from 521 to 312
Calculation steps:
[( 312 - 521 ) ÷ 521] x 100 = -40.12%
Formula
Percentage change = [(312 - 521) / 521] x 100
Subtract the new number by the original number
312 - 521 = -209
-209 ÷ 521 = -0.40115163147792704
-0.40115163147792704 x 100 = -40.12%