-60.43% is the change from 647 to 256
Calculation steps:
[( 256 - 647 ) ÷ 647] x 100 = -60.43%
Formula
Percentage change = [(256 - 647) / 647] x 100
Subtract the new number by the original number
256 - 647 = -391
-391 ÷ 647 = -0.6043276661514683
-0.6043276661514683 x 100 = -60.43%