-18.95% is the change from 512 to 415
Calculation steps:
[( 415 - 512 ) ÷ 512] x 100 = -18.95%
Formula
Percentage change = [(415 - 512) / 512] x 100
Subtract the new number by the original number
415 - 512 = -97
-97 ÷ 512 = -0.189453125
-0.189453125 x 100 = -18.95%