-15.01% is the change from 613 to 521
Calculation steps:
[( 521 - 613 ) ÷ 613] x 100 = -15.01%
Formula
Percentage change = [(521 - 613) / 613] x 100
Subtract the new number by the original number
521 - 613 = -92
-92 ÷ 613 = -0.1500815660685155
-0.1500815660685155 x 100 = -15.01%