-20.51% is the change from 512 to 407
Calculation steps:
[( 407 - 512 ) ÷ 512] x 100 = -20.51%
Formula
Percentage change = [(407 - 512) / 512] x 100
Subtract the new number by the original number
407 - 512 = -105
-105 ÷ 512 = -0.205078125
-0.205078125 x 100 = -20.51%