-47.27% is the change from 512 to 270
Calculation steps:
[( 270 - 512 ) ÷ 512] x 100 = -47.27%
Formula
Percentage change = [(270 - 512) / 512] x 100
Subtract the new number by the original number
270 - 512 = -242
-242 ÷ 512 = -0.47265625
-0.47265625 x 100 = -47.27%