-20.31% is the change from 512 to 408
Calculation steps:
[( 408 - 512 ) ÷ 512] x 100 = -20.31%
Formula
Percentage change = [(408 - 512) / 512] x 100
Subtract the new number by the original number
408 - 512 = -104
-104 ÷ 512 = -0.203125
-0.203125 x 100 = -20.31%