-6.33% is the change from 521 to 488
Calculation steps:
[( 488 - 521 ) ÷ 521] x 100 = -6.33%
Formula
Percentage change = [(488 - 521) / 521] x 100
Subtract the new number by the original number
488 - 521 = -33
-33 ÷ 521 = -0.06333973128598848
-0.06333973128598848 x 100 = -6.33%