-5.18% is the change from 521 to 494
Calculation steps:
[( 494 - 521 ) ÷ 521] x 100 = -5.18%
Formula
Percentage change = [(494 - 521) / 521] x 100
Subtract the new number by the original number
494 - 521 = -27
-27 ÷ 521 = -0.05182341650671785
-0.05182341650671785 x 100 = -5.18%