-61.6% is the change from 664 to 255
Calculation steps:
[( 255 - 664 ) ÷ 664] x 100 = -61.6%
Formula
Percentage change = [(255 - 664) / 664] x 100
Subtract the new number by the original number
255 - 664 = -409
-409 ÷ 664 = -0.6159638554216867
-0.6159638554216867 x 100 = -61.6%