-6.25% is the change from 512 to 480
Calculation steps:
[( 480 - 512 ) ÷ 512] x 100 = -6.25%
Formula
Percentage change = [(480 - 512) / 512] x 100
Subtract the new number by the original number
480 - 512 = -32
-32 ÷ 512 = -0.0625
-0.0625 x 100 = -6.25%