-18.36% is the change from 512 to 418
Calculation steps:
[( 418 - 512 ) ÷ 512] x 100 = -18.36%
Formula
Percentage change = [(418 - 512) / 512] x 100
Subtract the new number by the original number
418 - 512 = -94
-94 ÷ 512 = -0.18359375
-0.18359375 x 100 = -18.36%