-72.13% is the change from 915 to 255
Calculation steps:
[( 255 - 915 ) ÷ 915] x 100 = -72.13%
Formula
Percentage change = [(255 - 915) / 915] x 100
Subtract the new number by the original number
255 - 915 = -660
-660 ÷ 915 = -0.7213114754098361
-0.7213114754098361 x 100 = -72.13%