-60.06% is the change from 641 to 256
Calculation steps:
[( 256 - 641 ) ÷ 641] x 100 = -60.06%
Formula
Percentage change = [(256 - 641) / 641] x 100
Subtract the new number by the original number
256 - 641 = -385
-385 ÷ 641 = -0.6006240249609984
-0.6006240249609984 x 100 = -60.06%