-96.48% is the change from 512 to 18
Calculation steps:
[( 18 - 512 ) ÷ 512] x 100 = -96.48%
Formula
Percentage change = [(18 - 512) / 512] x 100
Subtract the new number by the original number
18 - 512 = -494
-494 ÷ 512 = -0.96484375
-0.96484375 x 100 = -96.48%